How to stop my dog from constantly chewing himself?

My dog is a westie cross with a miniature German schnauzer and is forever chewing his skin. It's so bad he makes himself bleed and the vets have run out of options. Is it just my dog? And is there anything we can do to stop it?

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).