Perhaps you should try some spelling variations:
chieu tinh » lieu tinh, chau tinh, kieu tinh
truong cao » truong dai
nhung cong » dung cong, thong cong, hang cong
trung hoc » trung quoc
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu tinh) OR (trieu tinh)) - hanh ((trung hoc) OR (truong cao)) nhung cong dan toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu tinh) OR (trieu tinh)) - hanh ((trung hoc) or (truong cao)) nhung cong dan toan cau~".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu tinh) OR (trieu tinh)) - hanh ((trung hoc) or (truong cao)) nhung cong dan toan cau*.