Perhaps you should try some spelling variations:
thanh trung » thanh tung
hoc thieu » toc thieu, hoc hien
trung cua » truong cua, trung tuan, trung cap
cua khong » hua khong, cua phuong, cua thuong
doc hieu » toc thieu, hoc hien
cong san » cong tac
than cau » toan cau, phan cau, than cap

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) OR (hoc thieu)) tinh - thanh trung cua khong ((huong dan) or (cong san)) than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc hieu) OR (hoc thieu)) tinh - thanh trung cua khong ((huong dan) OR (cong san)) than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) OR (hoc thieu)) tinh - thanh trung cua khong ((huong dan) or (cong san)) than cau".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) OR (hoc thieu)) tinh - thanh trung cua khong ((huong dan) or (cong san)) than cau*.