Perhaps you should try some spelling variations:
hanh tranh » hanh trinh, hanh trang, lanh tranh
hieu sang » chieu sang, hieu lang, hieu quang
cua nhung » va nhung
thanh hai » thanh phan, thanh hoa, thanh san
doc hieu » toc thieu, hoc thieu, hoc hien
nong san » cong san, dong san, trong san
nong dan » cong dan, nguong dan, huong dan

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 sang - ((hanh tranh) or (canh tranh)) cua nhung ((nong san) OR (nong dan)) thanh hai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - ((hanh tranh) OR (canh tranh)) cua nhung ((nong san) OR (nong dan)) thanh hai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu sang - ((hanh tranh) or (canh tranh)) cua nhung ((nong san) OR (nong dan)) thanh hai".
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - ((hanh tranh) or (canh tranh)) cua nhung ((nong san) OR (nong dan)) thanh hai*.