Perhaps you should try some spelling variations:
thanh trung » thanh tung
chiet tach » chieu sach
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » dung cong, thong cong, hang cong
trung va » truong va, trang va, trung ha
cong tan » cong tac, cong san, cong thanh
tran tap » toan tap, tran tan, tran tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chiet tach) or (chieu sang)) - thanh trung va nhung cong tan tran tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chiet tach) OR (chieu sang)) - thanh trung va nhung cong tan tran tap.
• Adding a wildcard symbol may retrieve word variants: hoc ((chiet tach) or (chieu sang)) - thanh trung va nhung cong tan tran tap*.