Just keep training him. When he nips, yelp and either you move to another room or you move him to another room for time-out for a few seconds. Also, teach "gently" when giving him a treat, only give him the treat when he takes it off you nicely. When I had my pup, I had tons of scratches and bites on my hand, and there was blood everywhere, every puppy owner goes through it, but they do learn. Keep training his commands as well.

__________________

I OWN A CHOCOLATE ROAN COCKER SPANIEL
RIP David xx Run free at the bridge. Love you always xx 19th February 2011
RIP Jack and Mickey xx Run free at the bridge. Love you forever xx 20th June 2011