Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
ky canh » ky anh, ky cach, ky danh
canh xa » canh va, canh tac, canh tay
hieu ve » hieu va, hieu van
cac thu » cach thuc, cac thoi
cac tu » cach tu, cac du, tac tu
vai va » mai va, dai va, hai va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky canh xa hoi. hieu ve ((cac tu) OR (cac thu)) ((van ban) or (van thanh)) vai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky canh xa hoi. hieu ve ((cac tu) OR (cac thu)) ((van ban) OR (van thanh)) vai va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky canh xa hoi. hieu ve ((cac tu) OR (cac thu)) ((van ban) or (van thanh)) vai va thiet".
• Adding a wildcard symbol may retrieve word variants: tu cac ky canh xa hoi. hieu ve ((cac tu) OR (cac thu)) ((van ban) or (van thanh)) vai va thiet*.