Perhaps you should try some spelling variations:
ban lanh » ban hanh, ban linh, ban anh
lanh hai » manh hai, thanh hai, lang chai
so triet » su triet, so thiet, bo triet
su sach » so sach, vu sach
ky dang » ky danh
xay hoi » xa hoi, tay hoi, cay phoi
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
duc ban » duc tan, duc van, dua ban
ve cac » va cac, vien cac
hai so » dai so, tai so, thai son

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)) xay hoi. hieu ve cac duc ban lanh hai so triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky dang) OR (ky nang)) xay hoi. hieu ve cac duc ban lanh hai so triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky dang) OR (ky nang)) xay hoi. hieu ve cac duc ban lanh hai so triet*.