Please use the search engine above, toward the top of the page: look up sensitive stomach, allergies, etc.
Also, consider what the homeopathic vets have to say http://www.vitalanimal.com
link for a homemade diet http://www.homeovet.net/dynamic/php/downloads/dog-c8470f2c75dbe4b683205c3919ee2310/dog_diet_complete.pdf
http://www.homeovet.net/content/lifestyle.html
Also, I know you have been back and forth to the regular vet , but have you considered seeing a specialist? Sometimes it makes a big difference.
