How can a use Blueprint to make vehicle AI that follow the player vehicle?

*edit, i used a dot product where the " . " node is (because i still dont know what that . is) and reversed the locations of player character and the vehicle, so i made vehicle location - player location and now it goes to player (whereas before it was going in the exact opposite direction)…

old question: same question as jjwisniewka… wahts that " . " node stand for