Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu manh » hieu nganh, dieu hanh, hien hanh
luan phan » luan van, luan hoan
canh dan » canh van, sanh dan, thanh dan
van phan » van phong, van thanh, van ban
dan va » doan va, dan ca, ban va

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

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