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]
(..) Diamonds. Bling. Crystals are frequently formed and found... ...in volcanic tubes. This tube could take us back up, right? - Uh-huh. - We're not far from the surface. - Uh-uh. - When we get out, I'm getting a Maserati. Money is not the only thing that matters, Sean. People matter too, you know. (..)2008 Journey to the Center of the Earth