Perhaps you should try some spelling variations:
thang long » thanh cong
doi chieu » doc hieu, doi chi, mot chieu
long thuc » luong thuc, long thuoc, cong thuc
thuc van » thuc vat, thuc dan, thuc va
van cong » van dong, van phong, phan cong
cong van » cong vang, cong san, song van
van phan » van phong, van thanh, luan 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 - thang long thuc van cong van phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (toc thieu)) sach - thang long thuc van cong van phan tu.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (toc thieu)) sach - thang long thuc van cong van phan tu*.