Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
quoc lan » quoc ban, nuoc luan, quoc quan
thai cua » than cua, tai cuc, tri cua
hieu van » hieu va, thien van, lieu va
duc manh » suc manh, duc anh, duc minh
tu sach » thu sach, su sach, te sach
xuc ban » duc ban, cuc ban, quoc ban
sach ky » sac ky, sach y, sach ty
van cac » van hac, van cau, van bac
nang ho » nang hoc, nang co, tang ho
cua tre » cua te, cuu tre, cua triet
ho hai » hoc hai, pho hai, cho 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 ho hai. hieu van cac ((((xuc ban) or (quoc lan))) or (duc manh)) hanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ho hai. hieu van cac ((((xuc ban) OR (quoc lan))) OR (duc manh)) hanh thai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ho hai. hieu van cac ((((xuc ban) or (quoc lan))) or (duc manh)) hanh thai cua tre*.