To Google or not to Google, this is the question

To Google or not to Google has become in the latest years a big question for researchers: immediate answers, but often thousands; sometimes pertinent, sometimes not reliable or too commercial-oriented. No doubt that Google always ''finds'' something and sometimes it is the only way, or it retrieves real pearls but where does it search? How can a researcher refine or limit the search? That is why we'll explore some Google features not so widely known, and other search engines with useful devices to perform a more efficient search in the biomedical field.