Deleting your search results doesn’t prevent Google from building a search history of you. Even start using DuckDuckGo and only searches from there doesn’t prevent this I guess as many sites use Google Custom Search and when you use an Android phone Google still tracks many of your searches doesn’t it? Therefore I use TrackMeNot (http://cs.nyu.edu/trackmenot) and Adnauseum (https://adnauseam.io/) as tools to block Google from profiling me. In stead of blocking it to track me, the TrackMeNot browser extension fires so many random searches to the Google search engine that my search profile is already infested with a plethora of random interest no company can create a serious profile of me I guess (and hope). The Adnauseum browser extension does basically the same with advertisements on websites. One advantage of this browser extension is that it hides adds for me and the other one is that it clicks them all so the advertisement companies have to pay to the site I visit while I actually haven’t visited them. Also, they can’t profile me as Adnauseum clicks every advertisement.