Perhaps you should try some spelling variations:
dinh viet » ninh viet, danh viet, trinh viet
cua triet » cua viet, su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, mang xa, ang xa
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, dua tren
ve cac » va cac, vien cac
dac va » duc va, day va, dai va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty xang xa hoi. hieu ve cac ((dac va) OR (dat va)) dinh viet ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty xang xa hoi. hieu ve cac ((dac va) OR (dat va)) dinh viet ((cua tre) OR (cua triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty xang xa hoi. hieu ve cac ((dac va) OR (dat va)) dinh viet ((cua tre) or (cua triet))*".