FBL3N help needed

Hi SAP Gurus,

I need to know the data extraction logic of tcode FBL3N as I have the requirement to develop a report program using the logic used in FBL3N.

The report program name of FBL3N is RFITEMGL. I tried to find the logic in debugging mode.. but no luck.. 😔

please help..

thanks and regrads,

Lucy