Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
hieu van » hieu va, thien van, lieu va
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
nam duc » nam duoc, pham duc, nam thuc
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cua te » cua tu

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