Sorry for confusion,
This Requirements is for another query.
I want A intersection B intersection C.
But I cann’t use filter because either user can provide A, B, C, AB, BC, CA or ABC.
So for filter one variable should be permanent which will used in function then we can apply others in filter.
So I decided different approach by getting
A, B, C, AB, BC, CA, ABC as per user, then find intersection of all these.