Perhaps you should try some spelling variations:
hanh lai » hanh lam, thanh lap, thanh loi
hanh tai » thanh tai, hang tai, hinh tai
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
han tai » hang tai, nhan tai, van tai
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, mang xa, ang xa
cua tre » cua te, cuu tre, cua triet

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 ty xang xa hoi. hieu van nam thuc dan ((hanh lai) or (((hanh tai) or (han tai)))) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty xang xa hoi. hieu van nam thuc dan ((hanh lai) OR (((hanh tai) OR (han tai)))) cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty xang xa hoi. hieu van nam thuc dan ((hanh lai) or (((hanh tai) or (han tai)))) cua tre*.