Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
cau xuc » cam xuc, cau luc, cau truc
va hanh » va thanh, va danh, ban hanh
va cau » van cau, va cac, va dau

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 ty lang xa hoi. lieu va cau xuc ((va hanh) or (van hanh)) ((ki su) OR (ky su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty lang xa hoi. lieu va cau xuc ((va hanh) OR (van hanh)) ((ki su) OR (ky su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty lang xa hoi. lieu va cau xuc ((va hanh) or (van hanh)) ((ki su) OR (ky su)) triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ty lang xa hoi. lieu va cau xuc ((va hanh) or (van hanh)) ((ki su) OR (ky su)) triet*.