You don't say how long you've had this dog, and your post makes it sound as if the vet didn't have concerns about her skin and coat now. If she was in such poor condition when you got her, give her time in her new clean environment with decent food and care to heal. A better coat may not come in till she's been through a shed and regrowth cycle. If you're feeding kibble, you might consider a supplement such a good quality fish oil.