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