I need to generate a pivot report based on the data from a subform but I need the ability to filter on two fields from the main form

For example:

Form A contains 2 keys fields:

Store

Store_Number

SubForm A -

Store_Name = Store - Store_Number

all numbers needed for pivot report   

I created a pivot report based on SubFormA but I need the ability to filter on FormA Store & Store_Number

Any ideas how to best accomplish this?