Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
thai cua » than cua, tai cuc, tri cua
nang hoc » nang doc, nang luc, dong hoc
duc manh » suc manh, duc anh, duc minh
quoc ban » quoc bao, quoc lan, quoc quan
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
nang ho » nang co, tang ho, nang cao
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) OR (nang hoc)) hai. hieu ve cac ((quoc ban) or (duc manh)) nhanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ho) OR (nang hoc)) hai. hieu ve cac ((quoc ban) OR (duc manh)) nhanh thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang ho) OR (nang hoc)) hai. hieu ve cac ((quoc ban) or (duc manh)) nhanh thai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang ho) OR (nang hoc)) hai. hieu ve cac ((quoc ban) or (duc manh)) nhanh thai cua tre*.