Perhaps you should try some spelling variations:
thanh trung » thanh tung
trung tran » trung tuan, trung thanh, trung tam
tran thong » toan thong, tran hong, tran trong
hieu manh » chieu xanh, hieu nganh, hien hanh
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu manh) OR (dieu hanh)) - thanh trung tran thong ((cong tan) or (cong san)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (dieu hanh)) - thanh trung tran thong ((cong tan) OR (cong san)) toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu manh) OR (dieu hanh)) - thanh trung tran thong ((cong tan) or (cong san)) toan cao*".