Perhaps you should try some spelling variations:
sach vuc » sach duoc, sach nuoc, sach truc
vuc nang » cuc nang, vu nang, chuc nang
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
cao hoi » cau hoi, co hoi, cao hoc
ban hoc » bang hoc, van hoc, bai hoc
va hanh » va thanh, va danh, ban hanh
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach vuc nang cao hoi. hieu van ban hoc ((va hanh) or (van hanh)) ((vai cua) OR (hai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach vuc nang cao hoi. hieu van ban hoc ((va hanh) OR (van hanh)) ((vai cua) OR (hai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach vuc nang cao hoi. hieu van ban hoc ((va hanh) or (van hanh)) ((vai cua) OR (hai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: su sach vuc nang cao hoi. hieu van ban hoc ((va hanh) or (van hanh)) ((vai cua) OR (hai cua)) triet*.