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db.collection.aggregate([{$match:{"contents.paragraphCleanText":"cleaned content 3"}},{$project:{_id:0,chapterNumber:1,contents:{$arrayElemAt:[{$filter:{input:"$contents",cond:{$eq:["$$this.paragraphCleanText","cleaned content 3"]}}},0]}}},{$project:{chapterNumber:1,paragraphNumber:"$contents.paragraphNumber","paragraphCleanText":"$contents.paragraphCleanText"}}])