Perhaps you should try some spelling variations:
trung tuan » trung thanh, tran tuan, truong thanh
cong thanh » dong thanh, cong trinh, truong thanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
hoc hieu » hoc thieu, hoc hien, doc hieu
cong tan » cong tac, cong san, cong ty
toan cau » 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: hoc hieu manh - thanh ((trung tuan) or (trung tam)) dung ((cong tan) OR (cong thanh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - thanh ((trung tuan) OR (trung tam)) dung ((cong tan) OR (cong thanh)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu manh - thanh ((trung tuan) or (trung tam)) dung ((cong tan) OR (cong thanh)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - thanh ((trung tuan) or (trung tam)) dung ((cong tan) OR (cong thanh)) toan cau*.