Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, nhieu tang
nhung cong » dung cong, thong cong, hang cong
hieu lang » hieu quang, nhieu tang, hieu van
tung cua » trung cua, tuong cua, tang cua
dung cua » dung luan, dung cho
cong tac » cong ty
tac khan » tac nhan, cac khoan, tac chuan
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu lang) OR (chieu sang)) - thanh ((tung cua) or (dung cua)) nhung cong tac khan cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (chieu sang)) - thanh ((tung cua) OR (dung cua)) nhung cong tac khan cap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu lang) OR (chieu sang)) - thanh ((tung cua) or (dung cua)) nhung cong tac khan cap".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) OR (chieu sang)) - thanh ((tung cua) or (dung cua)) nhung cong tac khan cap*.