title: How to find from multiple values in mongodb
body: <p>There is a collection in MongoDB like:</p>
  
  <pre><code>{
      "_id" : ObjectId("5bcc4c7d1e2c701be024de99"),
      "className" : "Class 10",
      "gradeLevel" : "10th",
      "subjectName" : "Math",
      "teacherId" : "abcd@gmail.com",
      "__v" : 0
  },
  {
      "_id" : ObjectId("5bd45277f5b9430013f4a604"),
      "className" : "Class 11",
      "gradeLevel" : "11th",
      "subjectName" : "Maths",
      "teacherId" : "abcd@gmail.com",
      "__v" : 0
  },
  {
      "_id" : ObjectId("5bd470fe452cb33af4b8407a"),
      "className" : "Class 10",
      "gradeLevel" : "12th",
      "subjectName" : "Math",
      "teacherId" : "abcd@gmail.com",
      "__v" : 0
  },
  </code></pre>
  
  <p>Now I want to fetch those documents with values of_id: 
  ObjectId("5bd45277f5b9430013f4a604"), ObjectId("5bd470fe452cb33af4b8407a").</p>
  
  <p>I am using mongoose and node.js. So please tell me is there any way to do this.</p>