What kind of puppy food is good for sensitive stomachs?

My puppy vomits a lot and my vet says that he is okay and recommends Purina One and Science Diet. I have been feeding him Purina but hear that both Purina and Science Diet are really bad for him. He is an English Bulldog and very thin. What kind of food is healthy and can put some weight on him, as well as be sensitive on his tummy. I'm thinking about Blue Buffalo.