[{"_id":"1","personalities":[{"personalName":"something","color":0,"total":0,"userId":""}]},{"_id":"2","personalities":[{"personalName":"other thing","color":0,"total":0,"userId":""}]},{"_id":"3","personalities":[{"personalName":"something","color":0,"total":0,"userId":""},{"personalName":"not something","color":0,"total":0,"userId":""}]}]

db.collection.find({"personalities.personalName":"something"})