Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
cong thanh » dong thanh, cong trinh, cong tan
hieu lang » chieu sang, hieu quang, nhieu tang
hanh hang » thanh hang, hang hang, hanh han
cua nhung » va nhung
hang cua » mang cua, hang ca, huong cua
cong san » cong tac
nhan tao » nhan tai, nhan dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu sach) or (hieu lang)) - hanh hang cua nhung ((cong san) or (cong thanh)) nhan tao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (hieu lang)) - hanh hang cua nhung ((cong san) OR (cong thanh)) nhan tao.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (hieu lang)) - hanh hang cua nhung ((cong san) or (cong thanh)) nhan tao*.