Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
hanh tranh » canh tranh, hanh trinh, hanh trang
tranh cua » doanh cua, manh cua
hang cong » dang cong, hang nong, bang cong
cua hang » cua dang, cua nhung, cua cong
tap toan » tap quan, bai toan
tap doan » tap quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chinh sach) or (chieu tinh)) - hanh tranh cua hang cong ((tap toan) OR (tap doan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chinh sach) OR (chieu tinh)) - hanh tranh cua hang cong ((tap toan) OR (tap doan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chinh sach) or (chieu tinh)) - hanh tranh cua hang cong ((tap toan) OR (tap doan)) cao".
• Adding a wildcard symbol may retrieve word variants: theo ((chinh sach) or (chieu tinh)) - hanh tranh cua hang cong ((tap toan) OR (tap doan)) cao*.