Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » thong cong, hang cong, nhung don
hieu manh » chieu xanh, hieu nganh, dieu hanh
dung cong » dung trong
trung va » truong va, trang va, trung ha
tan phan » toan phan, than phan, van phan
phan dau » phan tu, hang dau

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