If you think she only did it for the money, you haven't even 'scratched the surface'. [=there are many other factors, reasons, etc., involved]
Despite the 'surface' differences between the two candidates, they are very similar in most ways.
The tension between them is beginning to 'rise to the surface'. [=it is becoming easy to see]
(..) I'll be in the car. You might want to change your shirt. They're very sensitive to smell. The Mosasaurus was thought to have hunted near the surface of the water... where it preyed on anything it could sink its teeth into. Including turtles, large fish, even smaller Mosasaurus. (..)2015 Jurassic World