Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu qua, diep quang
hanh trinh » canh tranh, hanh chinh
hieu quan » hieu qua, lieu quan, thien quan
thanh lap » thanh san, phan lap, thanh hai
trinh va » trinh van, trinh vat, trinh ve
va trong » va truong, va thong, va tuong
cong tan » cong tac, cong san, cong thanh
than cap » khan cap, thanh cac, than cua

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 trinh va trong cong tan ((than cap) or (thanh lap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien ((hieu quang) OR (hieu quan)) - hanh trinh va trong cong tan ((than cap) OR (thanh lap)).
• Adding a wildcard symbol may retrieve word variants: thien ((hieu quang) or (hieu quan)) - hanh trinh va trong cong tan ((than cap) or (thanh lap))*.