Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dinh cau » dinh chau, dinh cuu, dinh cu
hieu van » hieu va, thien van, lieu va
dao duc » giao duc, tao duoc
cau cuu » cap cuu, cau cua, cau chu
va dinh » van dinh, va kinh, va tinh
hao duc » ho duc, cao duc, ha duc
sang xa » song xa, lang xa, sang ma
cuu tre » cua tre, cau tren, cau treo
y sang » _ sang, duy sang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) y sang xa hoi. hieu van ((hao duc) OR (dao duc)) va dinh cau cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) y sang xa hoi. hieu van ((hao duc) OR (dao duc)) va dinh cau cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) y sang xa hoi. hieu van ((hao duc) OR (dao duc)) va dinh cau cuu tre*".