These are quite good. What is missing now is the ability to either have the skills to paint details or to have the patience to paint details Don't know what you are lacking
The values of the landscape work fine, the colors of the character is also good and the anatomy of the dragon head is good too. If you'd just spend some more time on each of these they will turn out very solid - I'm sure.
You're asking for resources - http://www.ctrlpaint.com/
is a very good one. Also watch videos on Youtube. One video leads to the other and so on.