How Do You Create a Loop With Multiple Variables?

How do you make a loop with multiple variables? For example, what if I want my robot to go forward until all three of it’s line trackers see a black line? Or, what if I want my robot to back up until two limit switches are pressed? Is there any way of doing this in EasyC, and if so, how would I go about doing that?

while ( Var1 != 0 && Var2 != 0 && Var3 != 0 )
//code here

&& links conditions together