Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
hanh dai » hanh tai, hanh dao, vanh dai
su sach » so sach, vu sach
sach va » sach xa, sach ha, sach dao
va nang » van nang, da nang, cam nang
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
cua te » cua tu
o hoi » co hoi, o hai, o hoa
o hoc » co hoc, mo hoc, so hoc

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 nang ((o hoi) OR (o hoc)). 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 nang ((o hoi) OR (o hoc)). hieu va nham thuc va hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach va nang ((o hoi) OR (o hoc)). hieu va nham thuc va hanh dai cua te*.