Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
canh trinh » canh tranh, hanh trinh, canh tinh
hoc thieu » toc thieu, hoc hien
trinh va » trinh van, trinh vat, trinh ve
cong van » cong vang, song van, cong tan
cong san » cong tac
tuan cau » toan cau, quan cau, tuan cu
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 - canh trinh va dung ((cong van) or (cong san)) tuan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - canh trinh va dung ((cong van) OR (cong san)) tuan cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - canh trinh va dung ((cong van) or (cong san)) tuan cau*.