Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh di » hanh vi, hanh de, hang di
thuc va » thuc dan, thuc day
sach xa » sach dao, sach nha, sach bai
cua tuc » cua duc, cua tu, cua thuoc
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
di cua » dai cua, doi cua, de cua
va cau » van cau, va cac, va dau

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 xa ((nang xa) or (nang x)) hoi. hieu va cau ((thuc va) or (thuc vat)) hanh di cua tuc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach xa ((nang xa) OR (nang x)) hoi. hieu va cau ((thuc va) OR (thuc vat)) hanh di cua tuc.
• Adding a wildcard symbol may retrieve word variants: toc sach xa ((nang xa) or (nang x)) hoi. hieu va cau ((thuc va) or (thuc vat)) hanh di cua tuc*.