Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh trang » thanh trung, canh tranh, minh trang
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, thong cong, hang cong
hieu sang » chieu sang, hieu lang, nhieu tang
cua nhung » va nhung
san thanh » ban thanh, van thanh, son thanh
thanh cao » thanh ca, thanh cac, thanh thao
cong san » cong tac

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu sang) OR (hieu quang)) - ((hanh trang) or (hanh trinh)) cua nhung cong san thanh cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu sang) OR (hieu quang)) - ((hanh trang) OR (hanh trinh)) cua nhung cong san thanh cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu sang) OR (hieu quang)) - ((hanh trang) or (hanh trinh)) cua nhung cong san thanh cao*".