Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu qua, diep quang
hieu quan » hieu qua, lieu quan, thien quan
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cap » khan cap, thanh lap, thanh cac
tinh va » tich va, trinh van, trinh vat
hanh va » hang va, hanh vi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thien ((hieu quang) or (hieu quan)) - hanh ((tinh va) or (hanh va)) trong cong tan than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien ((hieu quang) OR (hieu quan)) - hanh ((tinh va) OR (hanh va)) trong cong tan than cap.
• Adding a wildcard symbol may retrieve word variants: thien ((hieu quang) or (hieu quan)) - hanh ((tinh va) or (hanh va)) trong cong tan than cap*.