Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
thai cua » than cua, tai cuc, tri cua
tu sach » thu sach, su sach, te sach
duc van » duc va, duc tan, duc manh
xuc ban » duc ban, cuc ban, quoc ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
hoc hai » hoc dai, hoc bai, hoc tai
ho hai » pho hai, cho hai, ho hap
ve cac » va cac, vien cac

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