Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
lang xa » lang ha, dang xay, lang van
nam tuc » nam thuc, nam truc, nam thuoc
va danh » va dinh, va dan, va hanh
danh va » doanh va, hanh va, anh va
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
nam tu » nam thu, nam thuc
va cua » va chua, via cua, ca cua

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 lang xa hoi. hieu van ((nam tuc) or (nam tu)) va danh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) y lang xa hoi. hieu van ((nam tuc) OR (nam tu)) va danh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) y lang xa hoi. hieu van ((nam tuc) or (nam tu)) va danh va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) y lang xa hoi. hieu van ((nam tuc) or (nam tu)) va danh va cua tre*.