Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
vu sach » vu bach, su sach, vu khach
ty hang » ty xang, thi hang, thu hang
ly hang » ly quang
cua tre » cua te, cuu tre, cua triet
ve cac » vien cac
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ((ty hang) OR (ly hang)) x hoi. hieu ((ve cac) OR (va cac)) duc va hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ((ty hang) OR (ly hang)) x hoi. hieu ((ve cac) or (va cac)) duc va hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: vu sach ((ty hang) OR (ly hang)) x hoi. hieu ((ve cac) or (va cac)) duc va hanh vi cua tre*.