Perhaps you should try some spelling variations:
tinh doi » trinh doc, trinh do, tinh hoc
te sach » toc sach
sach va » sach xa, sach ha, sach dao
doi cua » dai cua, hoi cua
va tinh » may tinh
va cham » va chat, va tham
cua tre » cua te, cuu tre, cua triet
tay hoi » tay ho, tao hoi, tay thai
mai hoi » mai khoi, dai hoi, lai hoi
va mang » va nang, va lang, va hang
loc va » hoc va, luc va
va cai » va cac, va bai, va dai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach va mang ((mai hoi) or (tay hoi)). hieu ((va cai) or (va cham)) loc va tinh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach va mang ((mai hoi) OR (tay hoi)). hieu ((va cai) OR (va cham)) loc va tinh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach va mang ((mai hoi) or (tay hoi)). hieu ((va cai) or (va cham)) loc va tinh doi cua tre*.