Perhaps you should try some spelling variations:
thieu mien » thieu nien, thieu bien, hieu hien
hoc sach » hoc sinh, hoc cac, hoc anh
toc sach » doc sach, thuoc sach, nuoc sach
sang mai » sang ma, sang tai, lang mai
mien bac » vien bach, dien ban, gian bac
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
ky sang » ky nang, ky dang, ky tang
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (toc sach)) ky sang mai hoi. thieu mien bac xuc va thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (toc sach)) ky sang mai hoi. thieu mien bac xuc va thanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (toc sach)) ky sang mai hoi. thieu mien bac xuc va thanh di cua tre*.