Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
doi chieu » doc hieu, doi chi, mot chieu
cong thuc » cong tac
thuc hang » thuc hanh, thu hang, phuc hang
hang cong » dang cong, hang nong, bang cong
cong phan » cong nhan, cong khan, chong phap
phan phan » phap phan, phan phat, than phan

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 - thong cong thuc hang cong phan phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (toc thieu)) sach - thong cong thuc hang cong phan phan tu.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (toc thieu)) sach - thong cong thuc hang cong phan phan tu*.