Perhaps you should try some spelling variations:
tinh cao » tinh lao, tinh chat, tinh cach
so sach » so sanh, bo sach, hoc sach
su viet » so viet
va tinh » may tinh
cao luc » bao luc, cao duc, cao suc
su tien » su kien, su hien, tu tieng
hang ca » hang va, nang cao, hang tai
ty hang » ly hang, ty xang, thi hang
co sach » bo sach, cuon sach, hoc sach
ca hoi » cau hoi, cua hoi, xa hoi
luc va » duc va, tuc va, loc va
va cao » va cac, va co, va dao

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ty hang ca hoi. lieu va cao luc va tinh cao ((su viet) OR (su tien))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (co sach)) ty hang ca hoi. lieu va cao luc va tinh cao ((su viet) or (su tien))~".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (co sach)) ty hang ca hoi. lieu va cao luc va tinh cao ((su viet) or (su tien))*.