Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
ky mang » ky nang, ke mang, ky dang
mang da » mang dat, mang dau, mang xa
cau tuc » cau tu, cau luc, cau phuc
ca viet » va viet, co viet, hoa viet
vai ca » vai cac, vai cua, bai ca

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 mang da khoa. lieu va ((cau tuc) OR (cau truc)) gia thanh vai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky mang da khoa. lieu va ((cau tuc) OR (cau truc)) gia thanh vai ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky mang da khoa. lieu va ((cau tuc) OR (cau truc)) gia thanh vai ca viet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky mang da khoa. lieu va ((cau tuc) OR (cau truc)) gia thanh vai ca viet*.