Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sang » chieu sang, thieu khang, thieu quang
hanh tranh » canh tranh, hanh trinh, hanh trang
hoc thieu » toc thieu, hoc hien
dang nong » dang cong, hang nong, tang nong
cua dang » cua cong, cua ban
san toan » van toan, dan toan, manh toan

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 - ((hanh tranh) or (thanh trung)) cua dang nong ((san toan) or (tinh toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - ((hanh tranh) OR (thanh trung)) cua dang nong ((san toan) OR (tinh toan)) cao.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - ((hanh tranh) or (thanh trung)) cua dang nong ((san toan) or (tinh toan)) cao*.