What I've understood is that search engines are not as magical as they are claimed to be by media and others who don't know. As I understood it, links to pages have to be crafted in a certain way for the search engine to even find the page. There was talk at sometime in steemit that if you searched with a tag from google you would get nothing as steemit was not in some way informing google that pages with that tag exists trough it. I won't go deeper as I barely know even this so you have to ask some more professional people.