Includes the same table unable to filter

[gaiapuffo]

Hi,

I have a query like this

Aaa::Module::Classification.unscoped.includes(:root_classification)

So I includes the same table...
My table have these fields

root_classication name_classification...
the problem is that in searchable_columns I can make

searchable_columns ||= ['Aaa::Module::Classification.name','Aaa::Module::Classification.name']
When the user insert the name of the classification in the search field
I filter always in base of the name of the classification and never in base of the name root_classication.

This is because the query give a alias to the second table.
I try to make

searchable_columns ||= ['aaa_module_classifications.name','root_classifications_aaa_module_classifications.name']

but i have the error uninitialized constant