Welcome to YT!! So glad to have you here.
Lots of people seem to be battling this right now. My male has had some problems with this - you might want to use an oatmeal shampoo. I posted a thread & another member posted amazing pix of her dog - you can see them here:
http://www.yorkietalk.com/forums/sho...d.php?t=104481
what she used & was recommended by her vet was NuSalTshampoo and Relief Creme Rinse (which I know vetamerica.com sells & maybe Petsmart) -- the results she had were impressive. I wanted to buy this, but was in a rush & instead bought locally some Tropiclean Oxy Oatmeal Shampoo & Oxy Med Treatment Rinse
http://www.tropiclean.net/tropiclean_index.html - we have good results with this, but I still want to try the NusalT
Missing Link is a great product & we have had good results with it - but to improve the coat I would recommend something with fish oil & vitamin E - a product a lot of people use is Eicosaderm - also available from vetamerica. I'm waiting for some to arrive, because although Bubba's skin has improved with the oatmeal shampoo, I think this might give us the boast we're looking for.
You can use the search option here on YT & search for: Eicosaderm & read what others have to say about the product.
Would love to see pix of your little one. Hope you stick around. This is a great community filled with fun, knowledgeable yorkie owners.