Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc ban » thuoc ban, thuc dan, thu ban
ban hanh » ban hang
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, nang ma
hanh di » hanh vi, hanh de, hang di
cua cay » cua cac
di cua » dai cua, doi cua, de cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ty) OR (sach thu)) nang xa hoi. hieu van nam thuc ban hanh di cua cay~.
• Adding a wildcard symbol may retrieve word variants: vu ((sach ty) or (sach thu)) nang xa hoi. hieu van nam thuc ban hanh di cua cay*.