Perhaps you should try some spelling variations:
trung tuan » trung thanh, trung tam, tran tuan
nhung cong » dung cong, thong cong, hang cong
hieu cach » hieu cac, chieu sach, hieu ca
trung cua » truong cua, trung cap, dung cua
hoc hieu » hoc thieu, hoc hien, doc hieu
dan toan » van toan, dan than, manh toan
dan chan » dan gian, dan ca, van chat

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu cach - thanh ((trung cua) OR (trung tuan)) nhung cong ((dan toan) or (dan chan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cach - thanh ((trung cua) OR (trung tuan)) nhung cong ((dan toan) OR (dan chan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu cach - thanh ((trung cua) OR (trung tuan)) nhung cong ((dan toan) or (dan chan)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - thanh ((trung cua) OR (trung tuan)) nhung cong ((dan toan) or (dan chan)) cau*.