Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
hieu lang » chieu sang, hieu quang, nhieu tang
van phong » van dong, hai phong
doi hieu » doi chieu, doc hieu, doi hien
van hang » van khang, van hoang, van thang
van tuan » van quan, van ban, anh tuan
va hang » va nang, va lang, va hanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi hieu lang - canh trinh ((va hang) OR (van hang)) cong ((van tuan) or (van phong)) cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - canh trinh ((va hang) OR (van hang)) cong ((van tuan) OR (van phong)) cac*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi hieu lang - canh trinh ((va hang) OR (van hang)) cong ((van tuan) or (van phong)) cac*".