Perhaps you should try some spelling variations:
cong thuong » hang thuong
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
thanh dung » thanh duong, thanh tung, thanh hung
manh toan » thanh toan, anh tuan, tinh toan
dung cua » dung luan, dung cho
dan toan » van toan, dan than, xuan toan

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 quang)) - thanh dung cua cong thuong ((dan toan) OR (manh toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu quang)) - thanh dung cua cong thuong ((dan toan) OR (manh toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sang) or (hieu quang)) - thanh dung cua cong thuong ((dan toan) OR (manh toan)) cao".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (hieu quang)) - thanh dung cua cong thuong ((dan toan) OR (manh toan)) cao*.