Perhaps you should try some spelling variations:
ban hanh » ban hang
cham duc » pham duc, cham soc, pham duy
lang van » dang van, tang van, hoang van
duc ban » duc tan, duc van, dua ban
vu cham » va cham, vu kham, tu cham
dang ky » dang y, dan ky, dong ky
su dang » su dung
lang xa » lang ha, dang xay
hieu vu » hieu va, hieu ve, hieu su
vi cua » vai cua
di cua » dai cua, doi cua, de cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su dang ky ((lang xa) or (lang van)) hoi. hieu vu cham duc ban hanh ((vi cua) OR (di cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su dang ky ((lang xa) OR (lang van)) hoi. hieu vu cham duc ban hanh ((vi cua) OR (di cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su dang ky ((lang xa) or (lang van)) hoi. hieu vu cham duc ban hanh ((vi cua) OR (di cua)) triet".
• Adding a wildcard symbol may retrieve word variants: su dang ky ((lang xa) or (lang van)) hoi. hieu vu cham duc ban hanh ((vi cua) OR (di cua)) triet*.