As Ajay put it, F4IF_INT_TABLE_VALUE_REQUEST is the standard FM that is used to program a Search Help.
Remember that you can create a F4 value request by creating a DDIC for F4 as well, if you want it to be assoiciated with teh DDIC.
Resort to the Fm mentioned above only if this has to be for the program ONLY.
You just need to populate the values that need to appear when you press F4 into an internal table. Ofcourse u will have to give the field name and other details.
Remember 2 reward suitable points.