Perhaps you should try some spelling variations:
hieu tinh » chieu tinh, lieu tinh, kieu tinh
tranh cua » doanh cua, manh cua
tong cong » trong cong, cong cong, dung cong
doc hieu » toc thieu, hoc thieu, hoc hien
cua tong » cua cong, cua dong, cua nong
cong tan » cong tac, cong san, cong thanh
tran ban » tranh ban, toan ban, tran bai
tran van » luan van

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 - canh tranh cua tong cong tan ((tran ban) or (tran van))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu tinh - canh tranh cua tong cong tan ((tran ban) OR (tran van)).
• Adding a wildcard symbol may retrieve word variants: doc hieu tinh - canh tranh cua tong cong tan ((tran ban) or (tran van))*.