Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
hieu van » hieu va, thien van, lieu va
van nham » van nam, van nhan, van tham
hanh dai » hanh tai, hanh dao, vanh dai
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
sach v » sach va, sach y, sach vay
sach 2 » sach y
nang o » nang co, nang ho, nang ro
cua te » cua tu
o hai » co hai, so hai, o lai

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 v) OR (sach 2)) nang o hai. hieu van nham thuc va hanh dai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach v) OR (sach 2)) nang o hai. hieu van nham thuc va hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: su ((sach v) OR (sach 2)) nang o hai. hieu van nham thuc va hanh dai cua te*.