Google knows many things about you that even your girlfriend doesn’t. Google tracks your online activities through cookies and web history.
All your online searches are tracked by Google in its web history unless you have not paused it.
While Google may claim that they won’t share these information with third parties, but the reality is that they actually do. To show more targeted ads of various companies specific to your searches, they use your web privacy information.
Here is a funny take on Google Store.