Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
hanh trang » thanh trung, hanh trinh, minh trang
hoc thieu » toc thieu, hoc hien
dung cong » dung trong
cong tinh » cong trinh, cong vinh, long tinh
toan ban » van ban
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 - ((hanh trang) or (canh tranh)) va dung cong tinh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - ((hanh trang) OR (canh tranh)) va dung cong tinh toan ban*.