Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
hieu van » hieu va, thien van, lieu va
thai cua » than cua, tai cuc, tri cua
van cac » van hac, van cau, van bac
xuc ban » duc ban, cuc ban, quoc ban
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
tang ho » tang cho, tung ho, tang ha
nang ho » nang hoc, nang co, nang cao
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: tu sach ky ((nang ho) or (tang ho)) hai. hieu van cac ((xuc ban) or (duc va)) hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ho) OR (tang ho)) hai. hieu van cac ((xuc ban) OR (duc va)) hanh thai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang ho) or (tang ho)) hai. hieu van cac ((xuc ban) or (duc va)) hanh thai cua tre*.