Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thieu sang » chieu sang, thieu khang, hieu lang
tang thanh » dang thanh, trung thanh, hoang thanh
thanh dung » thanh duong, thanh tung, thanh hung
manh tang » manh thang, manh tung, anh tang
dung cong » dung trong
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sang) OR (thieu quang)) - manh tang thanh dung cong ((dan toan) or (van toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu quang)) - manh tang thanh dung cong ((dan toan) OR (van toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (thieu quang)) - manh tang thanh dung cong ((dan toan) or (van toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (thieu quang)) - manh tang thanh dung cong ((dan toan) or (van toan)) cao*.