Perhaps you should try some spelling variations:
cuon sach » duong sach, cuoc cach, co sach
cac thoi » cac toi, cac hop, cac tro
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
thoi va » hoi va, thai va, tho va
va hang » van hang, va nang, va lang
doi cua » dai cua, hoi cua
ve cac » va cac, vien cac
di cua » dai cua, de cua, do 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) or (cuon sach)) ky nang x ho. hieu ve cac thoi va hang ((di cua) OR (doi cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (cuon sach)) ky nang x ho. hieu ve cac thoi va hang ((di cua) OR (doi cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (cuon sach)) ky nang x ho. hieu ve cac thoi va hang ((di cua) OR (doi cua)) triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (cuon sach)) ky nang x ho. hieu ve cac thoi va hang ((di cua) OR (doi cua)) triet*.