You can greatly narrow down your search results with the NOT operator. If you get too many responses, try adding NOT clauses using keywords from the sites you don’t want to be returned. You can add more NOT keywords if you need to screen out more sites.
However, remember that most search engines implement the NOT operator as a minus sign, so that for example if you want to say “NOT keyword” you need to type “-keyword”. For example, the following search will block any page that contains the words “art”, “car”, or “auto“, maximizing the chances that the pages returned will be about live mustang horses.
If you are getting a lot of irrelevant sites from the same Internet domain, then you can filter them all at once with the URL option by adding the domain name to the NOT clause. For example, the following search will block any site with the word “motorcycle” in its URL.
horse AND mustang AND -art AND -car AND -auto and -inurl:motorcycle