Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhung cong » thong cong, hang cong, nhung don
hieu lang » chieu sang, hieu quang, nhieu tang
hanh than » hanh han, hanh nhan, hanh phan
dung cong » dung trong
than cua » nhan cua, thai cua, ban cua
tan han » tan nhan, tran han, tan van
han tap » han tai, toan tap, nhan tai

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 than cua ((nhung cong) OR (dung cong)) tan han tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (hieu lang)) - hanh than cua ((nhung cong) OR (dung cong)) tan han tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sach) or (hieu lang)) - hanh than cua ((nhung cong) OR (dung cong)) tan han tap".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (hieu lang)) - hanh than cua ((nhung cong) OR (dung cong)) tan han tap*.