Form is not refreshing

Hi All,
 
I have a aspx page which is searching for items from database. If I search for something and find them and then try to search something else, it is still showing the old entry. It does not even tell me whether it has found anything or not like it should.
 
Can anyone please help me.
 
My code is:
protected void Page_Load(object sender, EventArgs e)
    {
        txtName.Focus();
    }
 
    private void GridViewCustomers_BindData()
    {
 
        // Data connection to Database
        if (txtName=null)
        {
            lblNoResultsMsg.Text += "Please enter search details. ";
     &n ...