Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
tu sach » thu sach, su sach, te sach
tai cua » thai cua, tai cuc, tri cua
anh tai » hanh tai, anh thai, vanh tai
van anh » van thanh, tuan anh, van minh
xuc van » duc van, luc van, xuc ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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