title: mongoose how to find all data from object?
body: <p>Just I want to find all data that have the same ID of an object but is not working </p>
  
  <pre><code>   app.get("/admin/phase/:level", function(req,res){
  
              Level.findOne({_id: req.params.level},function(err,onelevel){
              console.log(onelevel._id)
              Semster.find({level: onelevel._id},function(err,semster){
  
                      Module.find({semster: semster._id } , function(err , modules){
                      console.log(semster)
                          res.render("semster",{onelevels: onelevel, semsters: semster, modules: modules})})})})});
  </code></pre>