Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
thi hanh » thi thanh
ve chat » va chat, van chat
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
ty hang » ly hang, ty xang, thi hang
xuc va » duc va, tuc va, luc va
ve tai » te tai, de tai, le tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ty hang) or (thi hanh)) xa hoi. hieu ((ve tai) or (ve chat)) xuc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty hang) OR (thi hanh)) xa hoi. hieu ((ve tai) OR (ve chat)) xuc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty hang) or (thi hanh)) xa hoi. hieu ((ve tai) or (ve chat)) xuc va hanh vai cua tre*.