Although you set your PPC ads to appear on certain phrases (and combinations), people still find your ads through specific phrases they typed.
These are search variants. They have always been a part of the important feedback loop of adding and testing keywords, but recently there's been a hitch.
Google isn't sharing all of the searches that trigger your ads. Those details are an important part of PPC campaign improvement. In this video we explain the situation and show you a workaround.