Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
canh tran » canh tranh, hanh trang, banh trang
doc hieu » toc thieu, hoc thieu, hoc hien
tran van » luan van
van dung » van dong, xay dung, tin dung
cong van » cong vang, cong san, cong tan
song van » hoang van, trong van, duong van

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu xanh - canh tran van dung ((cong van) OR (song van)) bat dau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - canh tran van dung ((cong van) OR (song van)) bat dau".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh tran van dung ((cong van) OR (song van)) bat dau*.