Perhaps you should try some spelling variations:
hanh lai » hanh lam, hanh tai, thanh lap
sach thu » sach thue, sach thieu, sach tham
lai cua » dai cua, hai cua, lai chau
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
co thuc » do thuc, co thua, mo thuc
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
sach tu » cach tu, sach ty, sach uu
va co » vo co
x hoi » xa hoi, x ho, 5 hoi
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: te ((sach tu) or (sach thu)) nang ((x hoi) OR (o hoi)). hieu va co thuc va hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach tu) OR (sach thu)) nang ((x hoi) OR (o hoi)). hieu va co thuc va hanh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach tu) or (sach thu)) nang ((x hoi) OR (o hoi)). hieu va co thuc va hanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach tu) or (sach thu)) nang ((x hoi) OR (o hoi)). hieu va co thuc va hanh lai cua tre*.