Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
dang cong » dung cong
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan ban » van ban
va dang » van dang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: chao ((chieu sang) OR (hieu lang)) - ((canh tranh) or (thanh trung)) va dang cong dan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: chao ((chieu sang) OR (hieu lang)) - ((canh tranh) OR (thanh trung)) va dang cong dan toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "chao ((chieu sang) OR (hieu lang)) - ((canh tranh) or (thanh trung)) va dang cong dan toan ban".
• Adding a wildcard symbol may retrieve word variants: chao ((chieu sang) OR (hieu lang)) - ((canh tranh) or (thanh trung)) va dang cong dan toan ban*.