Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tang » hanh trang, anh tang, hanh mang
tang cua » mang cua, hang cua, tang luan
nong tan » nong dan, nong san, nong van
cong tan » cong tac, cong san, cong thanh
tran ban » tranh ban, tran van, toan ban

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: hoc ((chieu xanh) OR (hieu lang)) - hanh tang cua cong ((nong tan) OR (cong tan)) tran ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) or (hieu lang)) - hanh tang cua cong ((nong tan) OR (cong tan)) tran ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) or (hieu lang)) - hanh tang cua cong ((nong tan) OR (cong tan)) tran ban*.