Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
dang cong » dung cong
tranh va » tranh van, trang va, trinh va
cong tac » cong ty
tac phan » tac pham, tai phan, tac phat
phan dau » phan tu, hang dau
va dang » van dang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((thieu sang) OR (chieu sang)) - canh tranh va dang cong tac phan dau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((thieu sang) OR (chieu sang)) - canh tranh va dang cong tac phan dau".
• Adding a wildcard symbol may retrieve word variants: toc ((thieu sang) OR (chieu sang)) - canh tranh va dang cong tac phan dau*.