Perhaps you should try some spelling variations:
nang lai » nang tai, mang lai, nang cai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
lai hoi » dai hoi, lai hoa, lai roi
qua bai » qua ban, qua hai, qua cai
cua tre » cua te, cuu tre, cua triet
bao va » bao ve, tao va, ban va
cua tu » cua tuc, cua su, cua cu
bo va » do va, so va, co va

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 ky nang lai hoi. hieu qua bai ((bo va) or (bao va)) hanh vi ((cua tre) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang lai hoi. hieu qua bai ((bo va) OR (bao va)) hanh vi ((cua tre) OR (cua tu)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang lai hoi. hieu qua bai ((bo va) or (bao va)) hanh vi ((cua tre) or (cua tu))*.