Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
sang xa » song xa, lang xa, sang ma
hieu ve » hieu va
cac tuc » cac toc, cac tu, cac tac
va danh » va dinh, va dan, va hanh
lai cua » hai cua, lai chau, thai cua
y sang » _ sang, duy sang
tuc va » thuc va, truc va, tuc xa

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 y sang xa hoi. ((hieu ve) or (hieu van)) cac tuc va danh ((lai cua) OR (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y sang xa hoi. ((hieu ve) OR (hieu van)) cac tuc va danh ((lai cua) OR (dai cua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y sang xa hoi. ((hieu ve) or (hieu van)) cac tuc va danh ((lai cua) OR (dai cua)) tre*".