Function modules copy from standard FM?

Hi All,

I am copying FM CS_BOM_EXPL_MAT_V2 into ZCS_BOM_EXPL_MAT_V2 for some calculation.

I already copied the Function group CSS4 into ZCSS4 but when I m using ZCS_BOM_EXPL_MAT_V2 in my program I am not

getting the right BOM.

Where I am worng plz let me know?

Thanks and Regards

Steve