Search algorithms can't fight a semantic-level threat, they are just blind term-to-content conversion, like e.g. regex doesn't care if it finds something bad. Google can't use more expensive algorithms that actually can classify and understand the content, so their solution to this is human censors/curators. They get shamed regularly, and with recent youtube crisis(advertisers started to pull out) they probably started to take this issue seriously. https://www.theguardian.com/technology/2016/dec/04/google-de...