Anime Studio enables you to be creative, but it is only a tool. If you need to improve your drawing skills, there are several resources that can help. The listed resources are skewed toward mainly cartooning and animation instead of traditional types of drawing.
Drawing characters that have life and personality is an essential skill and the following books can help hone these skills:
Creating Characters with Personality: For Film, TV, Animation, Video Games and Graphic Novels by Tom Bancroft and Glen Keane
All About Techniques in Drawing for Animation Production by Sergi Camara
Cartoon Cool: How to Draw New Retro-Style Characters by Christopher Hart
Cartooning: Character Design by Walter ...