Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, cuoc cach, cuon sach
cao trung » cao truong, tao trung, bao trung
hoc sach » hoc sinh, hoc cac, hoc anh
trung va » truong va, trang va, trung ha
tu sach » thu sach, su sach, te sach
tai cua » thai cua, tai cuc, tri cua
han tai » hang tai, nhan tai, van tai
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
va han » va phan, van han, va hanh

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) or (((nuoc sach) OR (hoc sach)))) ky lang xa hoi. lieu va cao trung va han tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (((nuoc sach) OR (hoc sach)))) ky lang xa hoi. lieu va cao trung va han tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (((nuoc sach) OR (hoc sach)))) ky lang xa hoi. lieu va cao trung va han tai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (((nuoc sach) OR (hoc sach)))) ky lang xa hoi. lieu va cao trung va han tai cua tre*.