Perhaps you should try some spelling variations:
nang luong » nang song
chieu sach » chinh sach, chiet tach, chieu sang
luong quan » thong quan, duong qua
quan trong » gian trong
hieu lang » chieu sang, hieu quang, nhieu tang
cong san » cong tac
toan cau » toan cao, toan ban, toan tap
phan cau » phan dau, phan cac, phan tu

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)) - nang luong quan trong cong san ((toan cau) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (hieu lang)) - nang luong quan trong cong san ((toan cau) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (hieu lang)) - nang luong quan trong cong san ((toan cau) or (phan cau))*.