Perhaps you should try some spelling variations:
chieu xanh » chieu sang, chieu tinh, hieu manh
chieu sach » chinh sach, chiet tach, chieu sang
dung cong » dung trong
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan ban » van ban
tung ap » tung dan, tung bay, tung mai
tang ap » tang van, tang tai, tang dan

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: hoc ((chieu xanh) OR (chieu sach)) - thanh ((tung ap) OR (tang ap)) dung cong dan toan ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) OR (chieu sach)) - thanh ((tung ap) or (tang ap)) dung cong dan toan ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) OR (chieu sach)) - thanh ((tung ap) or (tang ap)) dung cong dan toan ban*.