Perhaps you should try some spelling variations:
phuong thao » phuong phap
phuong thuc » thuong thuc
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
hanh trang » thanh trung, canh tranh, hanh trinh
trang va » tran van, hang va
va lang » va nang, hoa lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: mot ((chieu sang) or (chieu sach)) - hanh trang va lang ((phuong thao) OR (phuong thuc)) van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: mot ((chieu sang) OR (chieu sach)) - hanh trang va lang ((phuong thao) OR (phuong thuc)) van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "mot ((chieu sang) or (chieu sach)) - hanh trang va lang ((phuong thao) OR (phuong thuc)) van ban".
• Adding a wildcard symbol may retrieve word variants: mot ((chieu sang) or (chieu sach)) - hanh trang va lang ((phuong thao) OR (phuong thuc)) van ban*.