@Chameloshi: this may sound annoying, but have you tried looking at an image of a face and copying it? That's how I practiced with facial expressions before I got into drawing. It takes A LOT of time to practice but it's worth the wait. You should try.

@W0LFB3AT5: I actually have have done it a couple times, but I think I gave up on the reference on some of them just to wing it. I think it's its because my drawing process is kind of unorthodox compared to proper drawing.