Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh lai » hanh lam, hanh tai, thanh lap
cham doc » cham soc, chat doc, chau doc
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
ty hang » ly hang, ty xang, thi hang
cuu tre » cau tren, cau treo
doc va » duoc va, hoc va, duc va
ma hoi » mai hoi, xa hoi, me hoi

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 ty hang ((ma hoi) or (ma hoa)). hieu ve cham doc va hanh lai ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty hang ((ma hoi) OR (ma hoa)). hieu ve cham doc va hanh lai ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: hoc sach ty hang ((ma hoi) or (ma hoa)). hieu ve cham doc va hanh lai ((cua tre) or (cuu tre))*.