Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
co sach » bo sach, cuon sach, hoc sach
van cau » van dau, van hau, van chat
cau toc » cac toc, cao toc, cau hoc
toc tay » toc thai
hanh di » hanh de, hang di, danh di

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 (co sach)) ky nang x ho. hieu van cau toc tay ((hanh di) OR (hanh vi)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (co sach)) ky nang x ho. hieu van cau toc tay ((hanh di) OR (hanh vi)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (co sach)) ky nang x ho. hieu van cau toc tay ((hanh di) OR (hanh vi)) su triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (co sach)) ky nang x ho. hieu van cau toc tay ((hanh di) OR (hanh vi)) su triet*.