[{"_id":ObjectId("602c03162077fb6064880efe"),"users":[{"_id":ObjectId("60136b272c1e946545da6204")},{"_id":ObjectId("609a80e3c548140e5859d6de")}]}]

db.collection.find({$and:[{"users._id":{$all:[ObjectId("609a80e3c548140e5859d6de"),ObjectId("60136b272c1e946545da6204")]}},{"users.2":{$exists:false}}]})