$elemMatch returns all subjects

[Miscellaneous]

Not sure where the issues arise from, but

e.g In a document I have stored an array with 100 card objects, I only desire to pull one card with id:20 from that document

From console 3.6, this do exactly that:
db.myCards.findOne({ user_id: x }, { cards: { $elemMatch: { id: 20 }}} );

But, from latest hapi-mongo-models, same line will return all cards in the array

[Miscellaneous]

Solved: use "fields" ...

db.myCards.findOne({ user_id: x }, { fields: { cards: { $elemMatch: { id: 20 }}}});