Select statement doesnt bring data after (-)

Question

User-1305858305 posted

Hello,

Trying to retrieve data from db. 

 cmd.CommandText = "SELECT [TopicName] FROM [Topics] where TopicName like '%' + @SearchText + '%' ";
                cmd.Parameters.AddWithValue("@SearchText", prefix);
                cmd.Connection = conn;
                conn.Open();
                using (SqlDataReader sdr = cmd.ExecuteReader())
                {
                    while (sdr.Read())
                    {
                        topics.Add(sdr["TopicName"].ToString());
                    }
                }

But if column contain dashes doesnt display after dashes. 
How can I achieve this?