It use Missing Link and it just does WONDERS for Hobbs' skin and coat! I highly recommend it. Hobbs is such a picky eater, but he just loves the Missing Link. He licks it off his food sometimes!
You also might want to try changing shampoos. Also, make sure you use a conditioner...it makes their hair soft and shiny! You may have to do trial and error with the shampoos until you find one you like.
Good luck!