Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
truc va » thuc va, thuc vat, trung va
va vanh » va van, va danh, va hanh
y nang » ly nang, v nang, may nang
va cau » van cau, va cac, va dau
dai su » dai sua, dai so, dan su

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (ky nang)) xa hoi. lieu va cau truc va vanh dai su triet~".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (ky nang)) xa hoi. lieu va cau truc va vanh dai su triet*.