Perhaps you should try some spelling variations:
nhiet tach » chiet tach
hanh trung » thanh trung, hanh trang, manh trung
hoc nhiet » hoc thiet, hoc nghien, hoc hien
trung su » trung vu, trong su, trung du
cong dan » cong tan, huong dan, cong dong
cong tac » 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 nhiet tach - hanh trung su dung ((cong dan) or (((cong san) or (cong tac)))) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc nhiet tach - hanh trung su dung ((cong dan) OR (((cong san) OR (cong tac)))) toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc nhiet tach - hanh trung su dung ((cong dan) or (((cong san) or (cong tac)))) toan cau*.