Interactive Report data overlapping or conflicting

Hi,     In Interactive programming report if on the first page(first list) of the output if I have data from 2 separate internal tables,one below the other how can they be made to work independent of each other so that the detail list(second list) output does not create conflict/overlapping between the output of list 1st and 2nd internal table  of the first list.The 2nd List Output displayed data should come from mutually exclusive table 1 and table 2 of the first list and show mutually exclusive of each other results on the second list.