Database
[{_id:ObjectId("649dbc85ff38d4464e5c0ee5"),user:"649dbc85ff38d4464e5c0ee2",friend:[{id:"649dbc81ff38d4464e5c0edd",name:"paco"},{id:"649dbc63ff38d4464e5c0ed8",name:"angel"}]},{_id:ObjectId("750dbc96ff49d5575e6c1ee6"),user:"750dbc96ff49d5575e6c1ee6",friend:[{id:"750dbc96ff49d5575e6c1edd",name:"luis"},{id:"750dbc96ff49d5575e6c1ed8",name:"hugo"}]}]
Query
db.collection.find({user:"649dbc85ff38d4464e5c0ee2"},{friend:{$elemMatch:{name:"paco"}}})