Perhaps you should try some spelling variations:
hanh hoi » hanh thoi, hanh noi, hanh hoa
thuc van » thuc vat, thuc dan, thuc hanh
so sach » so sanh, bo sach, co sach
hoi cua » hoi chuc
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
mang xa » lang xa, mang may, dang xay
hieu le » hieu ve, hieu he, hieu ly
sach v » sach va, sach y, sach 2
le nam » ly nam, he nam, le na

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 v ((mang xa) or (nang x)) hoi. hieu le nam ((thuc van) OR (thuc va)) hanh hoi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach v ((mang xa) OR (nang x)) hoi. hieu le nam ((thuc van) OR (thuc va)) hanh hoi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach v ((mang xa) or (nang x)) hoi. hieu le nam ((thuc van) OR (thuc va)) hanh hoi cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach v ((mang xa) or (nang x)) hoi. hieu le nam ((thuc van) OR (thuc va)) hanh hoi cua tre*.