Perhaps you should try some spelling variations:
hieu cua » hieu qua, dieu cua, bieu cua
luoc van » luoc can, luoc va, luc van
cac luoc » cac nuoc, cac cuoc, cac quoc
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
anh va » hanh va
anh ve » hanh ve, anh viet, thanh ve
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sach ty)) nang x hoi. hieu cua cac luoc van ((anh va) or (anh ve)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang x hoi. hieu cua cac luoc van ((anh va) OR (anh ve)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) nang x hoi. hieu cua cac luoc van ((anh va) or (anh ve)) cua tre*.