Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
cong thuc » cong tac
thuc dung » thuoc dung, thuy dung, tuc dung
dung cong » dung trong
cong van » cong vang, cong san, song van
van phan » van phong, van thanh, luan phan
phan lap » phan dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) or (toc thieu)) sach - thanh cong thuc dung cong van phan lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (toc thieu)) sach - thanh cong thuc dung cong van phan lap.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (toc thieu)) sach - thanh cong thuc dung cong van phan lap*.