Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
sach ky » sach ty, sach kem, sach hay
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
vi cua » vai cua, di cua
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: su ((((sach ky) OR (sach y))) or (sac ky)) nang x hoi. hieu van nam thuc va thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach ky) OR (sach y))) OR (sac ky)) nang x hoi. hieu van nam thuc va thanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((((sach ky) OR (sach y))) or (sac ky)) nang x hoi. hieu van nam thuc va thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((((sach ky) OR (sach y))) or (sac ky)) nang x hoi. hieu van nam thuc va thanh vi cua tre*.