Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
ky danh » ky anh
ky dang » ky nang
hieu ve » hieu va, hieu van
cac tuc » cac toc, cac tu, cac tac
ve cac » va cac, vien cac
vai va » mai va, dai va, hai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky danh) OR (ky dang)) xa hoi. hieu ve cac tuc ((van ban) or (van thanh)) vai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky danh) OR (ky dang)) xa hoi. hieu ve cac tuc ((van ban) OR (van thanh)) vai va triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky danh) OR (ky dang)) xa hoi. hieu ve cac tuc ((van ban) or (van thanh)) vai va triet*".