Perhaps you should try some spelling variations:
canh thanh » canh tranh, danh thanh, anh thanh
hieu cach » hieu cac, chieu sach, hieu ca
van hoang » van hoan, quan hoang, tran hoang
hoc hieu » hoc thieu, hoc hien, doc hieu
van hang » van khang, van thang, ban hang
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu cach - canh thanh ((van hang) OR (van hoang)) cong dan toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu cach - canh thanh ((van hang) OR (van hoang)) cong dan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - canh thanh ((van hang) OR (van hoang)) cong dan toan cao*.