Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
vien cac » vien bach, vien dai, vien da
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
ky sang » ky dang, ky tang, duy sang
ve cac » va cac
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky sang) or (ky nang)) ma hoi. hieu ((ve cac) OR (vien cac)) xuc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky sang) OR (ky nang)) ma hoi. hieu ((ve cac) OR (vien cac)) xuc va hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky sang) or (ky nang)) ma hoi. hieu ((ve cac) OR (vien cac)) xuc va hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky sang) or (ky nang)) ma hoi. hieu ((ve cac) OR (vien cac)) xuc va hanh vai cua tre*.