Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, nhieu tang
hanh tranh » canh tranh, hanh trinh, hanh trang
hieu lang » hieu quang, nhieu tang, hieu van
bang cong » bang song, hang cong, dung cong
dang cong » dung cong
tranh va » tranh van, trang va, trinh va
van phan » van phong, van thanh, luan phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sang) OR (hieu lang)) - hanh tranh va ((bang cong) or (dang cong)) van phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sang) OR (hieu lang)) - hanh tranh va ((bang cong) OR (dang cong)) van phan tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sang) OR (hieu lang)) - hanh tranh va ((bang cong) or (dang cong)) van phan tu".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sang) OR (hieu lang)) - hanh tranh va ((bang cong) or (dang cong)) van phan tu*.