Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
chieu tinh » trieu tinh, lieu tinh, chau tinh
hanh tranh » hanh trinh, hanh trang, lanh tranh
nhung cong » dung cong, thong cong, hang cong
cua nhung » va nhung
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan ban » van ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu tinh)) - ((hanh tranh) OR (canh tranh)) cua nhung cong tac toan ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (chieu tinh)) - ((hanh tranh) OR (canh tranh)) cua nhung cong tac toan ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu tinh)) - ((hanh tranh) OR (canh tranh)) cua nhung cong tac toan ban*.