Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hieu van » hieu va, thien van, lieu va
hanh tai » hang tai, han tai, hinh tai
tu sach » thu sach, su sach, te sach
cac ban » cac dan, cac van, can ban
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
cuc ban » cua ban, cuu ban, duc ban
van cam » van nam, van lam, van cau
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma 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 ma hoi. hieu van cam ((cuc ban) or (cac ban)) ((hanh tai) or (thanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ma hoi. hieu van cam ((cuc ban) OR (cac ban)) ((hanh tai) OR (thanh tai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ma hoi. hieu van cam ((cuc ban) or (cac ban)) ((hanh tai) or (thanh tai)) cua tre*.