Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu xanh » chieu sach, chieu sang, chieu tinh
nhung cong » dung cong, thong cong, hang cong
hieu manh » hieu nganh, dieu hanh, hien hanh
trung va » truong va, trang va, trung ha
tap toan » tap doan, tap quan, bai toan
tam toan » tam than, pham toan, tam thanh

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 manh) OR (chieu xanh)) - thanh trung va nhung cong ((tap toan) or (tam toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (chieu xanh)) - thanh trung va nhung cong ((tap toan) OR (tam toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu manh) OR (chieu xanh)) - thanh trung va nhung cong ((tap toan) or (tam toan)) tap".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu manh) OR (chieu xanh)) - thanh trung va nhung cong ((tap toan) or (tam toan)) tap*.