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]
(..) one for each champion... ...now lie on the bottom of the Black Lake. In order to win... ...each champion need only find their treasure and return to the surface. - Simple enough, except for this: - Put that in your mouth. They will have but one hour to do so, and one hour only. (..)2005 Harry Potter and the Goblet of Fire