Perhaps you should try some spelling variations:
cach thuc » anh thuc
dung cong » dung trong
quyen va » quyen van, luyen va, quyen vo
thu dung » thuy dung, thuc dung, thu dang
cac thu » cac thoi
ban vat » bang vat, ben vat, ban va
vat y » vat ly, vat _
y thu » ly thu, ky thu, y thuc

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

• Performing a fuzzy search may retrieve terms with similar spellings: quyen va ((cach thuc) or (cac thu)) đe co ban vat y thu dung cong~.
• If you are trying to use Boolean operators, they must be ALL CAPS: quyen va ((cach thuc) OR (cac thu)) đe co ban vat y thu dung cong.
• Adding a wildcard symbol may retrieve word variants: quyen va ((cach thuc) or (cac thu)) đe co ban vat y thu dung cong*.