Fetch FIT Reduced Subject Withholdable for current TRU

We have a custom extract, which is using Database item group - US_FIT_REDUCED_SUBJECT_WITHHOLDABLE_REL_NOCB_YTD, as attribute - FIT Reduced Subject Withholdable. This Database item group is fetching FIT Reduced Subject Withholdable for both TRU(SUM) if an employee moves from one legal entity to other in same year, how can we restrict to certain TRU, we also have TRU as parameter while submitting extract flow.