Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
hieu tinh » chieu tinh, kieu tinh, hieu binh
lieu tinh » trieu tinh, diep tinh, bien tinh
tranh va » tranh van, trang va, trinh va
cong dan » cong san, cong tan, huong dan
toan cau » toan cao, toan ban, toan tap
va lang » va nang, hoa lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu tinh) or (lieu tinh)) - canh tranh va lang ((cong dan) or (cong thanh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu tinh) OR (lieu tinh)) - canh tranh va lang ((cong dan) OR (cong thanh)) toan cau.
• Adding a wildcard symbol may retrieve word variants: doc ((hieu tinh) or (lieu tinh)) - canh tranh va lang ((cong dan) or (cong thanh)) toan cau*.