Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
chieu sang » chieu sach, chieu xanh, hieu lang
hoc chieu » hoc thieu, ho chieu, hoc hien
hanh tang » anh tang, hanh mang, hanh tung
luan dang » luan nang, luan danh, luan dong
nhan cau » nhanh cau, phan cau, nhan sau

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: hoc chieu sang - ((hanh tang) OR (hanh trang)) luan dang ((cong tac) OR (cong ty)) nhan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu sang - ((hanh tang) OR (hanh trang)) luan dang ((cong tac) or (cong ty)) nhan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc chieu sang - ((hanh tang) OR (hanh trang)) luan dang ((cong tac) or (cong ty)) nhan cau*.