Perhaps you should try some spelling variations:
lanh tranh » canh tranh, lan tranh, hanh trinh
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
lanh manh » lan anh, van manh, anh anh
cua thong » cua thuong, cua khong, cua tong
thanh cha » thanh ha, thanh nha, thanh phan
doi hieu » doi chieu, doc hieu, doi hien
cong tan » cong tac, cong san, cong thanh
than cap » khan cap, thanh lap, thanh cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi hieu lang - ((lanh manh) OR (lanh tranh)) cua thong cong tan ((thanh cha) or (than cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - ((lanh manh) OR (lanh tranh)) cua thong cong tan ((thanh cha) OR (than cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi hieu lang - ((lanh manh) OR (lanh tranh)) cua thong cong tan ((thanh cha) or (than cap))".
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - ((lanh manh) OR (lanh tranh)) cua thong cong tan ((thanh cha) or (than cap))*.