Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
vai cua » dai cua, hai cua, lai cua
va kinh » va tinh, qua kinh
va dinh » van dinh, va tinh, vu dinh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
ty hang » ly hang, thi hang, thu hang
ve cam » ve cham, ve cac, va cam

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 xang) or (ty hang)) xa hoi. hieu ve cam xuc ((va dinh) OR (va kinh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((ty xang) OR (ty hang)) xa hoi. hieu ve cam xuc ((va dinh) OR (va kinh)) vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((ty xang) or (ty hang)) xa hoi. hieu ve cam xuc ((va dinh) OR (va kinh)) vai cua tre".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((ty xang) or (ty hang)) xa hoi. hieu ve cam xuc ((va dinh) OR (va kinh)) vai cua tre*.