How to help my chihuahua with dry skin?

My dog has dry skin making her itch alot. I use oatmeal shampoo on her and comb her hair every other day. Does anyone have any tips in ways I can help my dog with dry skin?How to help my chihuahua with dry skin?
I agree with some of the other poster's answers. But something that will help right away is Vitamin E. Get Vitamin E tablets (the ones with the liquid inside) and rub a little bit on the dry areas. It is an instant moisturizer. I've used this on guinea pigs ears when dried and it helped within hours.How to help my chihuahua with dry skin?
Feed a high quality food not sold at grocery stores, and add an oil supplement to her diet.
Pura, Pit Bull, and Angie made great suggestions. I'll just add to it. After taking your dog to the vet [just a quick exam, in case he could have a skin problem, just in case], get him some good foods like Natural Balance or Eagle Pack. They're both sold at petco and offer fantastic ingredients. Canidae, sold at smaller pet shops, have good formulas for healthy coats, and Innova, Wellness, and Orijen are also great foods. Good luck. :)
Sometimes dry skin is due to food allergies. Many dogs are allergic to the grains used in off-the-grocery-store-shelf dog foods. Maybe you could switch to a high quality dog food such as Innova Evo, Eagle Natural Pack Holistic, or Canidae. Sometimes dry skin just happens to dogs in the winter for the same reason it happens to humans. We stay inside where the air is pretty well dried out from keeping the home heated. In the summer time, when it is warmer, the air is moister, and dry skin isn't as much of a problem. You can also try giving your dog fish oil. You can buy it in small containers with pump dispensers and just pump out a little bit over her food at each meal. She won't like it, so you'll have to just keep giving it to her and let HER choose whether to eat or not. She won't starve herself, believe me, even if it takes her three days to accept the oil. You could give her the fish oil in capsules wrapped in cheese, but the capsules are kind of large, so she'd probably bite into them and she wouldn't like that one little bit. And finally, after you give her an oatmeal shampoo, you could rub a little conditioner onto her skin, especially in the places not covered by fur, such as her belly and the pads of her paws.
A change in diet maybe in order. If you are feeding a super market brand of dog food that could be your issue, try getting a higher quality food.





Now a supplement that may help your dog's skin and coat is fish oil. Also flax seed oil is good too.
She may not be getting enough fatty acids in her diet. We had to find a good nutritional supplement made especially for better skin and coat in dogs for one of my Chihuahuas, and after a week, it did the trick. Make sure you're not bathing her too often, as it will strip the oils from her skin and coat.
Change the shampoo and try a moisturizing formula, also do not rub her dry but PAT her dry, make sure youa re not washing her too much and thus stripping the oils from her fur