Help with Heads

I've been trying to study heads and facial expressions a little more. Here is my most recent 30 minute class

https://imgur.com/a/RqmBXJh

I'm trying to see how I can simplify them to fit onto my figure drawings but still maintain their expressions, which is why I've been trying to draw them relatively small and on the one page. It feels very difficult for me, I strangely seem to understand the anatomy of the rest of the body much better than the face. I mainly have issues with the jaw and mouth and I struggle a lot when it comes to drawing females.

Any advice is welcome, whether it's something I'm doing wrong or something I can do to make the process more manageble :)

Thanks for your Imgur post on your faces and expressions, Michael99, just love them so much, in terms of solidity, and in terms of gesture, and in terms of anatomy; and the bone structure, and the muscle structure of the face. And as for the 30 second ones, I see a lot of straight lines in them, which, pardon my language, gives it some of the rigidity. Why don't you do more curves in the jaws that you're talking about to give those expressions some character? And do you know why?? It's as a result of doing yet another 5 minutes of 30 second sketches of expressions, then you will experiment more on your pencil (or stylus) mileage. Hope it can, shall, and will have been helpful.

Polyvios Animations

Hy, maybe you should draw from observations, 1min drawings draw a lot of poses but not only the head try to draww a full body, in the real life the head is alway with the rest of the body. So draw a full body, your not forced to details the head just like a mannequin with no details, and when you start to understand the how the head is hooked to the body and how it interract with you can draw full body in 5 min, and if you think you are stuck just add more time.

if you draw every days full body with head , i think that will help you to understad the form of the head and that will help you to understand easly the forms of the face. Don"t forget to start never draw from imagination, but a lot of observation to understand the face the forms the light ect...

I hope that will help you, i do theses exercices from a month and that reaky help me to draw ealsy faces.

I do recommend you