I was able to get the Partner Functions of a Product by using the Table: COMM_IL_PRDBP
SOURCEGUID - This takes the GUID of Product (You can get it from the table: COMM_PRODUCT)
LINK_PARTNER_FCT - Takes the Partner Function relationship ( You can get the value from SPRO->CRM->Basic Functions->Partner Processing->Define Partner Functions )
You will get the required Partner's GUID in DESTINGUID . You can get the Business partner from BUT000->PARTNER_GUID