Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
thuc dan » thuc hanh, hoc dan, thuc vat
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc day
doi cua » dai cua, hoi cua, dong cua
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang x hoi. hieu van nam ((thuc va) or (thuc dan)) thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang x hoi. hieu van nam ((thuc va) OR (thuc dan)) thanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang x hoi. hieu van nam ((thuc va) or (thuc dan)) thanh doi cua tre*.