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db.collection.aggregate([{$match:{$or:[{"age":{$lt:18},"marks":{$gte:90}},{"age":{$gte:18},$or:[{"qualification.masters.semester.subject.computer":{$gte:90}},{"qualification.masters.semester.subject.english":{$gte:90}},{"qualification.bachelors.semester.subject.computer":{$gte:90}},{"qualification.bachelors.semester.subject.english":{$gte:90}}]}]}},{$project:{"name":1,"_id":0}}])