Display only parent term if child-term not empty (have nodes) OR child-term of child-term not empty

How to display only parent term if child-term not empty (have nodes) OR child-term of child-term not empty

For example:

Computer

-Mouses (empty)
--Genius (not empty)
--Razor (not empty)

-Monitors (empty)

-keyboard(not empty)

I need to display in result:

-Mouses
-keyboard

Please help!