V: What did he say David?
D: I don't think he would want me to tell you.
V: What did he say?
D: I'm sorry that's confid - (gets pushed to the wall) - ential.
V: So help me God, I will find the cord that makes you run and then I will cut it.
V Desperate Now: What did he say?
D: He said - try harder.
They are undoubtedly talking about Peter Weyland and his life support. She wants to cut his support to stop taking orders from him. This way - she can inherit the company. Weyland's order are undoubtedly to find something that can prolong his life. After she had failed numerous times - or just met with no success, so David goes to consult with Weyland in his sleeping chamber. Weyland tells her to try harder. David passes the message along - however heart breaking it may be.