Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
dung cong » dung trong
tuong va » truong va, thuong va, luong va
van toan » van tuan, van tan, van thanh
van quan » van 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: ho ((chieu sang) OR (hieu lang)) - thanh tuong va dung cong ((van toan) or (van quan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu lang)) - thanh tuong va dung cong ((van toan) OR (van quan)) cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sang) OR (hieu lang)) - thanh tuong va dung cong ((van toan) or (van quan)) cao*".