Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, doc sach, thuoc sach
sach ty » sach y, sach tu, sach thu
nang xa » lang xa, nang ma, mang xa
va nham » va cham, va tham, va nha
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
de cua » le cua, te cua, dieu cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((nang xa) OR (nang x)) hoi. lieu va nham thuc va danh ((de cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang xa) OR (nang x)) hoi. lieu va nham thuc va danh ((de cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((nang xa) OR (nang x)) hoi. lieu va nham thuc va danh ((de cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang xa) OR (nang x)) hoi. lieu va nham thuc va danh ((de cua) or (dai cua)) tre*.