Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thu sach » tu sach, thuat sach, thuoc sach
giau cua » gian cua, gia cua, dieu cua
van anh » tuan anh, van minh
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
tang ma » tang van
cua tre » cua te, cuu tre, cua triet
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: thu sach ky ((tang ma) or (mang may)) hoi. hieu ve cac he ((van anh) or (van thanh)) giau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((tang ma) OR (mang may)) hoi. hieu ve cac he ((van anh) OR (van thanh)) giau cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((tang ma) or (mang may)) hoi. hieu ve cac he ((van anh) or (van thanh)) giau cua tre*.