Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
chieu xanh » chieu sach, chieu sang, chieu tinh
canh trinh » canh tranh, hanh trinh, canh tinh
nhung cong » dung cong, thong cong, hang cong
trinh vat » trinh van, trinh luat, sinh vat
vat nhung » va nhung, vap nhung, vai nhung
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan ban » van ban

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) or (chieu xanh)) - canh trinh vat nhung cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu xanh)) - canh trinh vat nhung cong san toan ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (chieu xanh)) - canh trinh vat nhung cong san toan ban*.