Perhaps you should try some spelling variations:
hieu quan » hieu qua, lieu quan, thien quan
hoang van » hang va
nang cong » nang song, dang cong, bang cong
cong dan » cong san, cong tan, huong dan
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu
tang va » trang va, tang van, thang va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu quan - hanh ((tang va) or (hoang van)) nang cong dan ((toan cau) OR (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu quan - hanh ((tang va) OR (hoang van)) nang cong dan ((toan cau) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu quan - hanh ((tang va) or (hoang van)) nang cong dan ((toan cau) OR (toan cao))".
• Adding a wildcard symbol may retrieve word variants: ho hieu quan - hanh ((tang va) or (hoang van)) nang cong dan ((toan cau) OR (toan cao))*.