Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
dau thuc » dan thuc, dai thuc, dam thuc
su sach » vu sach
hanh di » hanh vi, hanh de, hang di
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
va dau » va dao
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (so sach)) thu ((nang xa) or (lang xa)) hoi. lieu va dau thuc van hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) thu ((nang xa) OR (lang xa)) hoi. lieu va dau thuc van hanh di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) thu ((nang xa) or (lang xa)) hoi. lieu va dau thuc van hanh di cua tre*".