Perhaps you should try some spelling variations:
thu nhat » thu nhap, thu thuat, thu ha
dinh dat » dinh ket, dinh van, dinh lam
sach thu » sach thue, sach thieu, sach tham
dinh dai » sinh dai, dinh dao, dinh tai
hieu he » hieu ve, hiem he, hieu le
sach ky » sac ky, sach y, sach ty
tang ma » mang may, tang van
cua tre » cua te, cuu tre, cua triet
he nam » ha nam, nghe nam

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) or (sach thu)) tang ma hoa. hieu he nam thu nhat ((dinh dai) OR (dinh dat)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach thu)) tang ma hoa. hieu he nam thu nhat ((dinh dai) OR (dinh dat)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach thu)) tang ma hoa. hieu he nam thu nhat ((dinh dai) OR (dinh dat)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach thu)) tang ma hoa. hieu he nam thu nhat ((dinh dai) OR (dinh dat)) cua tre*.