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 san » cong tac
tran tap » tran tan, tran tuan, trang tai
toan tap » toan ban

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 san ((tran tap) OR (toan 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 san ((tran tap) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chiet tach) or (chieu sang)) - thanh trung va nhung cong san ((tran tap) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: hoc ((chiet tach) or (chieu sang)) - thanh trung va nhung cong san ((tran tap) OR (toan tap))*.