Perhaps you should try some spelling variations:
thanh hang » thanh hoang, thanh thang, tranh hang
nhung cong » dung cong, thong cong, nhung don
hieu lang » chieu sang, hieu quang, nhieu tang
hang cong » dang cong, hang nong, bang cong
vang quan » van quan, nang quan, tang quan
quan cau » quang cao, toan cau, quan ha

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((chinh sach) or (hieu lang)) - thanh hang va ((nhung cong) OR (hang cong)) vang quan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chinh sach) OR (hieu lang)) - thanh hang va ((nhung cong) OR (hang cong)) vang quan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chinh sach) or (hieu lang)) - thanh hang va ((nhung cong) OR (hang cong)) vang quan cau".
• Adding a wildcard symbol may retrieve word variants: doi ((chinh sach) or (hieu lang)) - thanh hang va ((nhung cong) OR (hang cong)) vang quan cau*.