Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
hanh dai » hanh tai, hanh dao, vanh dai
sach va » sach xa, sach dao, sach nha
sach ha » sach nha, sach han, sach xa
hieu va » lieu va, hieu qua
va nham » va cham, va tham, va nha
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
nang o » nang co, nang ho, nang ro
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach va) OR (sach ha)) nang o hoi. hieu va nham thuc va hanh dai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach va) OR (sach ha)) nang o hoi. hieu va nham thuc va hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: su ((sach va) OR (sach ha)) nang o hoi. hieu va nham thuc va hanh dai cua te*.