HCM(HR) - Modify standard Search help using BADI

Hi friends.

Functional asked me to add a new tab in standard search help of a field in PSV2 transaction.

Wen we click right button in a course and chgose second option (Create w/o Resources), there is a field (Organizer data) where user can choose between types (eg.: KI-Prospect, KU-Customer, O-Org. Unit, U-Company).

In this case, she wants a new search help to option "U-Company", where she want to it for searching Vendors for LFA1, returning field LIFNR to fill this field.

I found a BADI to do that, but I don't know how. I see this BADI accept to change a parameter like search help name and I think I must copy standard (Collective) search help but adding a net tab for vendor search.

I think I must add a new tab with a standard search help to get vendors, like XK01 transaction does in field LIFNR.

How to do that ?

thanks.

Glauco