[{"name":"Jon","surname":"Snow","workplace":"nights watch","location":"beyond the wall"},{"name":"Samwell","surname":"Tarly","workplace":"nights watch","location":"beyond the wall"},{"name":"Ned","surname":"Stark","workplace":"castle winterfell","location":"winterfell"},{"name":"Foo","surname":"Bar","workplace":"nowhere","location":"space and time"},{"name":"Sansa","surname":"Stark","workplace":"westros","location":"winterfell"}]

db.collection.aggregate([{$addFields:{"nameFilter":{$concat:["$name"," ","$surname"]},"locationFilter":{$concat:["$workplace"," ","$location"]}}},{$match:{nameFilter:{$regex:"stark",$options:"i"},locationFilter:{$regex:"winterfell",$options:"i"}}}])