Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
hien manh » hien hanh, tien manh, hieu manh
trinh vat » trinh van, trinh luat, sinh vat
vat lang » va lang, van lang, vat mang
nong dan » cong dan, nguong dan, huong dan
nong san » cong san, dong san, trong san
chan tu » phan tu, han tu, chon tu

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien manh - canh trinh vat lang ((nong dan) OR (nong san)) chan tu~".
• Adding a wildcard symbol may retrieve word variants: hoc hien manh - canh trinh vat lang ((nong dan) OR (nong san)) chan tu*.