Perhaps you should try some spelling variations:
cuon sach » duong sach, cuoc cach, co sach
hieu van » hieu va, thien van, lieu va
thuc day » thuc dan, thuc vat
danh di » danh du, xanh di, danh dien
thuc va » thuc vat, thuc dan
van cac » van hac, van cau, van bac
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: cuon sach y ((nang xa) or (nang ma)) hoi. hieu van cac ((thuc va) OR (thuc day)) danh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: cuon sach y ((nang xa) OR (nang ma)) hoi. hieu van cac ((thuc va) OR (thuc day)) danh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "cuon sach y ((nang xa) or (nang ma)) hoi. hieu van cac ((thuc va) OR (thuc day)) danh di cua tre".
• Adding a wildcard symbol may retrieve word variants: cuon sach y ((nang xa) or (nang ma)) hoi. hieu van cac ((thuc va) OR (thuc day)) danh di cua tre*.