Thanks comments guys!!!!! I'm so happy you guys said it.
derekmatthew - I know what you mean!!!! I feel the ZSphere method isn't useful either.
So I always use 3d-coat for make the topology while I hoping to improve the retopo method of ZBrush!!!!
teddy007kong - The clay look was made by mia material of mental ray.
I think it's a little bloatware. but if you OK, please try it out. You just might like it!