title: mongoose - How get value from related collection
body: <p>I have two collections :</p>
  <pre><code>const Schoolfeatures = Schema({
    _id: Schema.Types.ObjectId,
    Name: {
      type: String,
      required: true
    },
  });
  
  const Classfeatures = Schema({
    _id: Schema.Types.ObjectId,
    Name: {
      type: String,
      required: true
    },
    School: { 
      type: Schema.Types.ObjectId,
      ref: 'Schoolfeatures',
      required: true
    },
  });
  </code></pre>
  <p>And I try get list of classes:</p>
  <pre><code>await Classfeatures.find().populate({path: 'Schoolfeatures', select: 'schoolName' }) 
  </code></pre>
  <p>And I don't have school.name in list.</p>
  <p>How can I take school.name in classes list?</p>