Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
thanh thai » thanh hai, thanh tai, thanh thao
tu sach » thu sach, su sach, te sach
xuc van » duc van, luc van, xuc ban
cac xuc » cam xuc, cac nuoc, chat xuc
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
co hoi » co hoc, co loi
o hoi » o hoc, o hai, o hoa

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