Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
truc va » thuc va, thuc vat, trung va
tai cua » thai cua, tai cuc, dai cua
tuc va » thuc va, tuc xa, duc 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 ky lang xa hoi. hieu van nam ((tuc va) OR (truc va)) thanh ((tai cua) or (tri cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky lang xa hoi. hieu van nam ((tuc va) OR (truc va)) thanh ((tai cua) OR (tri cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky lang xa hoi. hieu van nam ((tuc va) OR (truc va)) thanh ((tai cua) or (tri cua)) te".
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. hieu van nam ((tuc va) OR (truc va)) thanh ((tai cua) or (tri cua)) te*.