Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu lang » chieu sang, hieu quang, nhieu tang
dung cong » dung trong
trinh va » trinh van, trinh vat, trinh ve
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tap » toan ban
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((chieu xanh) or (hieu lang)) - canh trinh va dung cong dan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu xanh) OR (hieu lang)) - canh trinh va dung cong dan toan tap.
• Adding a wildcard symbol may retrieve word variants: doi ((chieu xanh) or (hieu lang)) - canh trinh va dung cong dan toan tap*.