Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
thanh tung » thanh cong
hoc thieu » toc thieu, hoc hien
dung cong » dung trong
dan chan » dan gian, dan ca, van chat
van than » van thanh, van thang, van tuan
tung va » trung va, tuong va, dung va
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: hoc thieu sang - thanh tung va dung cong ((dan chan) or (van than)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - thanh tung va dung cong ((dan chan) OR (van than)) cao.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - thanh tung va dung cong ((dan chan) or (van than)) cao*.