Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu tinh » trieu tinh, lieu tinh, chau tinh
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
trung ha » trung hoc, trung tam, trung cap
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap

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

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