db={"events":[{"_id":"6138451fb3a7d9564a0229fd","title":"Event 1","cohortsGroups":[[{"_id":"6124beef59d728c82088fd59","name":"2022","type":"promotion"},{"_id":"6124bf2159d728c82088fd60","name":"Toronto","type":"city"}],[{"_id":"6124beef59d728c82088fd57","name":"2024","type":"promotion"},{"_id":"6124bf2159d728c82088fd68","name":"Tokyo","type":"city"}],]},{"_id":"6138451fb3a7d9564a0229fe","title":"Event 2","cohortsGroups":[[{"_id":"6124beef59d728c82088fd59","name":"2022","type":"promotion"}]]},{"_id":"6138451fb3a7d9564a0229fh","title":"Event 3","cohortsGroups":[[{"_id":"6124beef59d728c82088fd21","name":"2022","type":"promotion"},{"_id":"6124beef59d728c82088fd43","name":"Amsterdam","type":"city"}]]}]}

db.events.find({cohortsGroups:{$elemMatch:{$elemMatch:{_id:{$in:["6124beef59d728c82088fd59","6124bf2159d728c82088fd60"]}}}}})