Dog food for cockers

Question
Wat is the best dog food for an itchy cocker?  I currently have him on natural balance fish and sweet potatoes but still itches and has tiny, raised bumps of dry skin that sometimes feel wet if you scratch them off.  I wash him about once a week with high quality breed specific dog shampoo/conditioner used on show dogs and make sure he is dry.  Could it be the vit a responsive dermatosis?  He is 6 yo and I have given him Benadryl for his itching but doesn't control it.  So would like to find good recommended dog food and find out dosage for vit A?

Answer
Natural Balance isn't a very good food and I doubt it's the food anyway.  Usually it's inhalant allergies and dogs absorb allergens through their skin.

Benadryl is very ineffective with dogs and I strongly suggest trying Zyrtec.  Plain Zyrtec (not Zyrtec-D) - 10 mg. tablet once a day.

Try bathing him twice this week and finish off with a half water/half white vinegar rinse.
And start the Zyrtec.

Any bumps he can't lick you can use a drugstore antibiotic cream.  But NOT where he can get at it.

Let me know how that goes.  And has he had his thyroid checked?