Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van dinh » van minh, van dich, va dinh
thuc van » thuc vat, thuc dan, thuc va
can thuc » dan thuc, van thuc, cay thuc
dinh vi » dinh ve, dinh viet, dinh tri
van can » van canh, van ban, ban can
so sach » so sanh, bo sach, co sach
nang ma » tang ma, sang ma, nang cao
mang xa » lang xa, mang may, dang xay
nang xa » nang x, lang xa, ang xa
cua tre » cua te, cuu tre, cua triet
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: so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu van can thuc van dinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((((nang xa) OR (mang xa))) OR (nang ma)) hoi. hieu van can thuc van dinh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu van can thuc van dinh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu van can thuc van dinh vi cua tre*.