Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
phap hoc » phap hoan, phap mo, phap han
so sach » so sanh, bo sach, hoc sach
co sach » bo sach, cuon sach, hoc sach
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va phap » va phat, ban phap
hai cua » thai cua, hoi cua, lai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (co sach)) ty lang xa hoi. hieu va phap hoc dan thanh ((hai cua) OR (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ty lang xa hoi. hieu va phap hoc dan thanh ((hai cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (co sach)) ty lang xa hoi. hieu va phap hoc dan thanh ((hai cua) OR (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (co sach)) ty lang xa hoi. hieu va phap hoc dan thanh ((hai cua) OR (dai cua)) tre*.