Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
va triet » va thiet, va trien, ve triet
va thanh » gia thanh, ban thanh, va tinh
sach ky » sac ky, sach y, sach ty
van cau » van hau, van chat, toan cau
van dau » van dao, phan dau
tu sach » thu sach, su sach, te sach
dai va » mai va
o hai » co hai, so hai, o lai
o hoc » co hoc, mo hoc, so hoc

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 hoc) or (o hai)). hieu ((van cau) or (van dau)) duc va thanh dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((o hoc) OR (o hai)). hieu ((van cau) OR (van dau)) duc va thanh dai va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((o hoc) or (o hai)). hieu ((van cau) or (van dau)) duc va thanh dai va triet*.