Dependent Field: Support for multiple parents

I need to get child field terms from multiple parent field terms .
My scenario is ; Field A : University(parent), Field B : Faculty(Child).
Need to get all faculties from multiple universities which selected from parent field..
It shows only child terms (faculties) from first selected parent(university). I can't get faculties which belong to other universities.
Any help you can give would be greatly appreciated.
Thanks