Since there are two separate phrases, "do" is the correct verb tense for what you want to say. If there is only one phrase that includes an "and" or similar conjunction, to avoid verb confusion you would surround it with quotes. Example:
"What do "short sale" and "leveraged buy" mean when buying and selling stocks?
"What does "weighed and measured" mean when you say someone has been "weighed and measured"?
As in my first example, you can also put quotes around each of the terms you don't understand.
Lastly, I would say "I haven't encountered these terms before" instead of "I haven't found these terms before". "Found" implies that you actively went looking for them, while "encountered" means you just passively came across them.