I think you may use your still valid H4 visa stamp
for reentry of USA ,as my understand, usually US consulate only issue single entry H4 visa for Chinese passport holder,but if you have PR of third country ,you may get a multiple entry H4 visa.
for reentry of USA ,as my understand, usually US consulate only issue single entry H4 visa for Chinese passport holder,but if you have PR of third country ,you may get a multiple entry H4 visa.