Perhaps you should try some spelling variations:
thanh trung » thanh tung
nho hieu » nha hieu, nho sieu, nhu hieu
hoc taig » hoc tang, hoc dai, hoc tap
cong tac » cong ty
tac than » tac thanh, tam than, tac nhan
than cau » toan cau, phan cau, than cap
ho hieu » ho chieu, hoi hieu, co hieu
hoc tai » hoc dai, hoc tap, hoc bai

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) OR (nho hieu)) lang - thanh trung ((hoc taig) or (hoc tai)) cong tac than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho hieu) OR (nho hieu)) lang - thanh trung ((hoc taig) OR (hoc tai)) cong tac than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho hieu) OR (nho hieu)) lang - thanh trung ((hoc taig) or (hoc tai)) cong tac than cau".
• Adding a wildcard symbol may retrieve word variants: ((ho hieu) OR (nho hieu)) lang - thanh trung ((hoc taig) or (hoc tai)) cong tac than cau*.