Check your code here
DataRow dr = ds.Tables[0].Rows[0];
You are retrieving only 1st row from the dataset. Please loop through the dataset like below:
if(ds.Tables[0].Rows.Count > 0)
{
foreach(DataRow dr in ds.Tables[0])
{
string strHeading = Convert.ToString(dr["divhtml_heading"]);
string strContent = Convert.ToString(dr["divhtml_content"]);
}
}
Also check the query you are running in the database if it really returns 6 records. I am asking this as you have mentioned a condition in your query,
select * from content_managment where page_id = 1