Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
ky dang » ky danh
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
dai va » mai va

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 ((ky dang) OR (ky nang)) xa hoi. hieu va cac tuc van hanh dai va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky dang) OR (ky nang)) xa hoi. hieu va cac tuc van hanh dai va triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky dang) OR (ky nang)) xa hoi. hieu va cac tuc van hanh dai va triet*.