Look at the Constrained by function. See the documentation here: https://world.mendix.com/display/refguide6/Input+reference+set+selector
You should take a look at the constrained by setting, an unintuitive little setting that can be quite useful if you can wrap your head around it.
Take a look and drop me a line if you're having trouble implementing it.
Thx all! I learn more. But I can't set Selectable objects, I don't know how to write XPath constraint, how to write typeTwo is belong to typeOne.