Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh va » hanh vi
cua tre » cua te, cuu tre, cua triet
sai ky » sac ky
va hoe » van hoe, va hoc, va hoa
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach ty) or (sai ky)) hang va hoe. hieu van nam thuc va hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sai ky)) hang va hoe. hieu van nam thuc va hanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) or (sai ky)) hang va hoe. hieu van nam thuc va hanh va cua tre*.