Learning to draw deeply means using as many of the five senses as can be interpreted at once. You use your eyes, but do not close off the other senses - quite the opposite. All five play a part in the kind of observation you need to make. For example, you know the roughness of sandpaper by its touch, a flower by its smell, an orange by its taste, the difference between instruments by their sounds. You can know these things without seeing the objects at all. It is this involvement of the other senses with your ‘seeing’ that makes art what it is.
As we practice drawing in this way it becomes easier; the synapses and neural pathways learn new ways of connecting. In my own case, I 'feel' whatever I am focusing on in a textural way that is difficult to explain in words. Stone walls feel very different to grass, for example. Classical music feels different to dancers.
To experiment with this a little, find a nice juicy piece of fruit. Hold it in your hands and close your eyes. Squeeze it gently - how does it feel? How does it smell? If you lick it, what does the taste and texture do to your tongue? Does that bring up any memories for you? An orange might remind you of a Mediterranean holiday, sangria under the stars. An apple might bring up childhood scrumping adventures, feeding horses, apple pie....... let yourself wander for as long as you like.
When you really feel that you know much more about this piece of fruit than just the surface appearance, try drawing it, keeping the memories as vivid as possible. Try cutting it open and drawing the sections too, eat some of it and draw how THAT feels too.
Your drawings will encapsulate the feelings that arise as you draw, and that is what makes art such a potent form of communication. It can go so far beyond words and touch us much more deeply than any amount of explanation or rationalisation.