Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
can thuc » dan thuc, van thuc, cay thuc
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua
y nang » ky nang, ly nang, v nang
va can » va chan, va cac, va cao

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 y nang xa hoi. hieu va can thuc van hanh ((vai cua) or (hai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang xa hoi. hieu va can thuc van hanh ((vai cua) OR (hai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. hieu va can thuc van hanh ((vai cua) or (hai cua)) tre*.