Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
thieu sang » chieu sang, thieu quang, hieu lang
hanh tranh » canh tranh, hanh trinh, hanh trang
tranh cua » doanh cua, manh cua
dung cong » dung trong
cua dung » cua dang, cua dong, qua dung
san toan » van toan, dan toan, manh toan

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((thieu sang) OR (thieu khang)) - hanh tranh cua dung cong ((san toan) OR (tinh toan)) cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((thieu sang) OR (thieu khang)) - hanh tranh cua dung cong ((san toan) or (tinh toan)) cao~".
• Adding a wildcard symbol may retrieve word variants: toc ((thieu sang) OR (thieu khang)) - hanh tranh cua dung cong ((san toan) or (tinh toan)) cao*.