querying inside foreach

gistfile1.js

db.ratings.find().forEach(function(doc){
  
  var item = db.items.find({_id: doc.item_id})
  var ry = item.detail.ry

})


ITEM

{
    "_id" : ObjectId("5461c8f0426f727f16000000"),
    "n" : "The Shawshank Redemption",
    "detail" : {
      "ry": 1992
    }
}