Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trang » thanh trung, canh tranh, hanh trinh
hoc chieu » hoc thieu, ho chieu, hoc hien
dai khung » dai khong, dam khung, dai khoang
cong van » cong vang, cong san, song van
tuan ban » tuan bang, luan ban, quang ban
toan ban » van ban

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 trang ((dai khung) OR (dap ung)) cong van ((tuan ban) OR (toan ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu sang - hanh trang ((dai khung) or (dap ung)) cong van ((tuan ban) OR (toan ban))~".
• Adding a wildcard symbol may retrieve word variants: hoc chieu sang - hanh trang ((dai khung) or (dap ung)) cong van ((tuan ban) OR (toan ban))*.