Perhaps you should try some spelling variations:
thanh trong » thanh trung, tranh trong, hanh trong
hieu manh » chieu xanh, hieu nganh, dieu hanh
thien anh » thien danh, tien anh, thien thanh
trong su » trong san, trong thu, trong qua
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
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) or (thien anh)) - thanh trong su dung ((cong dan) OR (cong san)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (thien anh)) - thanh trong su dung ((cong dan) OR (cong san)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) or (thien anh)) - thanh trong su dung ((cong dan) OR (cong san)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) or (thien anh)) - thanh trong su dung ((cong dan) OR (cong san)) toan cau*.