Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
hanh trang » thanh trung, canh tranh, hanh trinh
trang vat » trang va, trang vai, tang vat
vat dung » van dung, va dung, viet dung
cong dan » cong tan, huong dan, cong dong
cong san » cong tac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu quang)) - hanh trang vat dung ((cong dan) OR (cong san)) van ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sang) or (hieu quang)) - hanh trang vat dung ((cong dan) OR (cong san)) van ban~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (hieu quang)) - hanh trang vat dung ((cong dan) OR (cong san)) van ban*.