Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hanh hai » thanh hai, nhanh hai, hang hai
thuc ban » thuoc ban, thuc dan, thu ban
tuc ban » truc ban, tu ban, tuc dan
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
ky danh » ky anh
ky dang » ky nang
ve cac » va cac, vien cac
hai va » hai van, thai va, hoi 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 dang) or (ky danh)) xa hoi. hieu ve cac ((tuc ban) OR (thuc ban)) hanh hai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky dang) OR (ky danh)) xa hoi. hieu ve cac ((tuc ban) OR (thuc ban)) hanh hai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky dang) or (ky danh)) xa hoi. hieu ve cac ((tuc ban) OR (thuc ban)) hanh hai va triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky dang) or (ky danh)) xa hoi. hieu ve cac ((tuc ban) OR (thuc ban)) hanh hai va triet*.