Closing a Page so the Parent Window displays the Default content

I have a Window, which default content is a menu system. when i press a button this code is triggered:

 Private Sub search_Click()
        Dim searchpage As New Search
        Me.Content = searchpage
    End Sub

this makes the window content display the search page. this is fine, now when i want to close the search page and display the default content, how do i do this?

and on the search page:

 Private Sub menu_click()
        ' Me.Close
        ' Me.Parent.
        ' Me.Content = vbNull
    End Sub

In WPF using VB.net in Visual Studio 2012.

Michael Booth