I agree with the poster who suggested changing your food. That will have the most profound impact. We feed grain-free foods and I love Wellness Core and Nature's Variety Instinct. We also add Taste of the Wild in there occasionally. If you find changing to a higher quality food doesn't help, I would suggest you add a good Omega-3 supplement. As per the recommendation of other YT users we started giving
Royal Coat Express 16oz, Ark Naturals Natural Products For Pets. Maggie just turned 5 and had some of the same problems with her coat. I have noticed a difference and we have only been feeding it for a couple of weeks!