Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
lanh hai » manh hai, thanh hai, lang chai
duc van » duc va, duc tan, duc manh
duc ban » duc tan, dua ban, duc man
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky danh
hai va » hai van, thai va, hoi va
ve cac » va cac, vien cac

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) or (duc van)) lanh hai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky dang) OR (ky nang)) xay hoi. hieu ve cac ((duc ban) OR (duc van)) lanh hai va 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) or (duc van)) lanh hai va triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky dang) OR (ky nang)) xay hoi. hieu ve cac ((duc ban) or (duc van)) lanh hai va triet*.