Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu xanh
chieu sang » chieu xanh, hieu lang, nhieu tang
canh trinh » hanh trinh, canh tinh, anh trinh
thang nong » thang long, hang nong, tang nong
han thang » van thang, han chang, nhanh thang
nong dan » cong dan, nong san, nguong dan
dan can » dan chan, dan canh, dan ca
can cau » van cau, ban cau, ca cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sach) OR (chieu sang)) - ((canh trinh) or (canh tranh)) han thang nong dan can cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (chieu sang)) - ((canh trinh) OR (canh tranh)) han thang nong dan can cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) OR (chieu sang)) - ((canh trinh) or (canh tranh)) han thang nong dan can cau".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sach) OR (chieu sang)) - ((canh trinh) or (canh tranh)) han thang nong dan can cau*.