Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
vu sach » vu bach, su sach, vu khach
co sach » bo sach, cuon sach, hoc sach
hieu ve » hieu va, hieu van
cac toc » cac toi, cac nuoc, cac thoi
hanh di » hanh vi, hanh de, danh di
hang di » hang doi, hang vi, hang dien
ve cac » va cac, vien cac
toc va » hoc va, toc ta, tuc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) or (co sach)) ky nang x ho. hieu ve cac toc va ((hanh di) OR (hang di)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (co sach)) ky nang x ho. hieu ve cac toc va ((hanh di) OR (hang di)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) or (co sach)) ky nang x ho. hieu ve cac toc va ((hanh di) OR (hang di)) cua triet".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (co sach)) ky nang x ho. hieu ve cac toc va ((hanh di) OR (hang di)) cua triet*.