I've been practicing

I've been drawing more humans but i feel that's really hard to me make it look like a real human, I added some lines to do the chest, and try to made the knees look less rigid. But i don't know how to improve it from here, anything else i do just make more weird. 
So a try to draw less humans forms and someone told me to look the "Preston Blair animation book",So I drew this bear from the book to improve my sense of proportion and depth.

[img]https://imgur.com/a/d4HOwJ1[/img]

https://imgur.com/a/d4HOwJ1