Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, doc sach, nuoc sach
tu nang » tru nang, tu nong, tu nano
nang xa » nang x, lang xa, nang ma
va nham » va cham, va tham, va nha
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
di cua » doi cua, de cua, do 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) OR (thuoc sach)) tu nang xa hoi. lieu va nham thuc va danh ((di cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) tu nang xa hoi. lieu va nham thuc va danh ((di cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) tu nang xa hoi. lieu va nham thuc va danh ((di cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) tu nang xa hoi. lieu va nham thuc va danh ((di cua) or (dai cua)) tre*.