I'm not sure i understand the issue.
I have visited your search at:
typed "cave" in the keywords text box.
I go to the Carvers Cave detail page
When i click the browsers back button I am prompted to Resubmit the form. This is because the action that loaded the results initially was a form submit. If i click yes, it shows the previous results.
the only way to get around the prompt to resend the form, would be to change the forms method to GET instead of using POST.