Database
[{skill:["python","csharp"],name:"Person A"},{skill:["php","python"],name:"Person B"},{skill:["python","css"],name:"Person C"},{skill:["css"],name:"Person D"},{skill:["javascript"],name:"Person E"}]
Query
db.collection.find({$expr:{$ne:[{$setIntersection:[["python","css"],"$skill"]},[]]}})