Perhaps you should try some spelling variations:
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
nam thuc » nam thuoc, am thuc, nam thu
hieu van » hieu va, thien van, lieu va
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach ty, sach kem
nang xa » lang xa, nang ma, mang xa
vi cua » vai cua, di 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 ky) or (sach y)) ((nang xa) OR (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)) ((nang xa) OR (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)) ((nang xa) OR (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)) ((nang xa) OR (nang x)) hoi. hieu van nam thuc va thanh vi cua tre*.