Is there possible to configure expect string.

Hello,

Of course you can set "Receive String/expect string" in your monitor:

Specifies the regular expression representing the text string that the monitor looks for in the returned resource. The most common receive expressions contain a text string that is included in an HTML file on your site. The text string can be regular text, HTML tags, or image names.

So in your case you have to se an regular epression.