diff --git a/documentation/src/main/asciidoc/migration/index.asciidoc b/documentation/src/main/asciidoc/migration/index.asciidoc
index 48bfa2f400b..474b4547a16 100644
--- a/documentation/src/main/asciidoc/migration/index.asciidoc
+++ b/documentation/src/main/asciidoc/migration/index.asciidoc
@@ -207,6 +207,7 @@ In Hibernate Search 6, constants are provided through classes whose name ends wi
 * `org.hibernate.search.backend.lucene.cfg.LuceneIndexSettings`
 * `org.hibernate.search.backend.elasticsearch.cfg.ElasticsearchBackendSettings`
 * `org.hibernate.search.backend.elasticsearch.cfg.ElasticsearchIndexSettings`
+* `org.hibernate.search.backend.elasticsearch.aws.cfg.ElasticsearchAwsBackendSettings`
 
 [[configuration-property-reference]]
 === [[_configuration_property_reference]] Configuration property reference
@@ -240,6 +241,30 @@ Hibernate Search 6 will automatically turn entities to documents
 and hold documents in memory until the transaction commit.
 +
 See also link:{hibernateSearchDocUrl}#mapper-orm-indexing-manual[this section of the documentation].
+`hibernate.search.default.elasticsearch.aws.*`::
+The syntax for configuring AWS authentication changed slightly in Hibernate Search 6.
++
+In short, the following configuration in Hibernate Search 5:
+[source]
+----
+hibernate.search.default.elasticsearch.aws.signing.enabled = true
+hibernate.search.default.elasticsearch.aws.region = us-east-1
+hibernate.search.default.elasticsearch.aws.access_key = AKIDEXAMPLE
+hibernate.search.default.elasticsearch.aws.secret_key = wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY
+----
++
+Will look like this in Hibernate Search 6:
+[source]
+----
+hibernate.search.backend.aws.signing.enabled = true
+hibernate.search.backend.aws.region = us-east-1
+hibernate.search.backend.aws.credentials.type = static
+hibernate.search.backend.aws.credentials.access_key_id = AKIDEXAMPLE
+hibernate.search.backend.aws.credentials.secret_access_key = wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY
+----
++
+Other types of credentials are available in Hibernate Search 6,
+see link:{hibernateSearchDocUrl}#backend-elasticsearch-configuration-aws[this section of the documentation]
 `hibernate.search.default.elasticsearch.connection_timeout`::
 Hibernate Search 6 equivalent: `hibernate.search.backend.connection_timeout`.
 +
@@ -1964,7 +1989,7 @@ As to migrating existing complex queries, let's consider the query below:
 
 [source, JAVA]
 ----
-MySearchParameters params = ...;
+MySearchParameters searchParameters = ...;
 FullTextEntityManager fullTextEntityManager = Search.getFullTextEntityManager( em );
 QueryBuilder qb = fullTextEntityManager.getSearchFactory()
         .buildQueryBuilder().forEntity( Book.class ).get();
@@ -1978,14 +2003,18 @@ if ( searchParameters.getSearchTerms() != null ) {
             .matching( searchParameters.getSearchTerms() )
             .createQuery() );
 }
-if ( searchParameters.getGenre() != null ) {
-    junction.must( qb.keyword().onField( "genre" )
-            .matching( searchParameters.getGenre() ) );
-}
 if ( searchParameters.getMaxBookLength() != null ) {
     junction.must( qb.range().onField( "pageCount" )
             .below( searchParameters.getMaxBookLength() ) );
 }
+if ( !searchParameters.getGenres().isEmpty() ) {
+    BooleanJunction junction2 = qb.bool();
+	for ( Genre genre : searchParameters.getGenres() ) {
+        junction2.should( qb.keyword().onField( "genre" )
+                .matching( genre ) );
+	}
+	junction.must( junction2.createQuery() );
+}
 
 org.apache.lucene.search.Query luceneQuery = junction.createQuery();
 
@@ -2000,7 +2029,7 @@ It would look like this in Hibernate Search 6:
 
 [source, JAVA]
 ----
-MySearchParameters params = ...;
+MySearchParameters searchParameters = ...;
 SearchSession session = Search.session( entityManager );
 List<Book> hits = searchSession.search( Book.class )
         .where( f -> f.bool( b -> {
@@ -2010,23 +2039,28 @@ List<Book> hits = searchSession.search( Book.class )
                         .matching( searchParameters.getSearchTerms() )
                         .defaultOperator( BooleanOperator.AND ) );
             }
-            if ( searchParameters.getGenre() != null ) {
-                b.must( f.match().field( "genre" )
-                        .matching( searchParameters.getGenre() ) );
-            }
             if ( searchParameters.getMaxBookLength() != null ) {
                 b.must( f.range().field( "pageCount" )
                         .atMost( searchParameters.getMaxBookLength() ) );
             }
+            if ( !searchParameters.getGenres().isEmpty() ) {
+                b.must( f.bool( b2 -> {
+                    for ( Genre genre : searchParameters.getGenres() ) {
+                        b2.should( f.match().field( "genre" )
+                                .matching( genre ) );
+                    }
+                } ) );
+            }
         } ) )
-        .fetchHits( params.getPageIndex() * params.getPageSize(), params.getPageSize() );
+        .fetchHits( searchParameters.getPageIndex() * searchParameters.getPageSize(),
+                searchParameters.getPageSize() );
 ----
 
 Alternatively, if for some reasons predicate objects are necessary:
 
 [source, JAVA]
 ----
-MySearchParameters params = ...;
+MySearchParameters searchParameters = ...;
 SearchSession session = Search.session( entityManager );
 SearchPredicateFactory pf = session.scope( Book.class ).predicate();
 List<SearchPredicate> predicates = new ArrayList<>();
@@ -2037,25 +2071,32 @@ if ( searchParameters.getSearchTerms() != null ) {
             .defaultOperator( BooleanOperator.AND )
             .toPredicate() );
 }
-if ( searchParameters.getGenre() != null ) {
-    predicates.add( pf.match().field( "genre" )
-            .matching( searchParameters.getGenre() )
-            .toPredicate() );
-}
 if ( searchParameters.getMaxBookLength() != null ) {
     predicates.add( pf.range().field( "pageCount" )
             .atMost( searchParameters.getMaxBookLength() )
             .toPredicate() );
 }
+if ( !searchParameters.getGenres().isEmpty() ) {
+    predicates.add( f.bool( b -> {
+        for ( Genre genre : searchParameters.getGenres() ) {
+            b.should( f.match().field( "genre" )
+                    .matching( genre ) );
+        }
+    } )
+            .toPredicate() );
+}
+
+SearchPredicate topLevelPredicate = pf.bool( b -> {
+    b.must( f.matchAll() );
+    for ( SearchPredicate predicate : predicates ) {
+        b.must( predicate );
+    }
+} );
 
 List<Book> hits = searchSession.search( Book.class )
-        .where( f -> f.bool( b -> {
-            b.must( f.matchAll() );
-            for ( SearchPredicate predicate : predicates ) {
-            	b.must( predicate );
-            }
-        } )
-        .fetchHits( params.getPageIndex() * params.getPageSize(), params.getPageSize() );
+        .where( topLevelPredicate )
+        .fetchHits( searchParameters.getPageIndex() * searchParameters.getPageSize(),
+                searchParameters.getPageSize() );
 ----
 
 [[queries-reference]]