Funnel is a sequence of pages (path) of a site and last page this series must be goal page. It is set by webmaster that a customer go through this path to complete a goal.
Access your Google analytics account. Go to Admin. Find and set up a conversion goal. Once you have a goal you create a funnel with the intermediate steps.
It might ignored those query strings and only see main file name.There is another easy alternative you can try. Create a custom thank you page, something like "thankyou.php" or "success.html" and put all your thank you message and your Google Analytic code there.You can then set your form to redirect to your custom thank you page instead of displaying the default success message.I believe that should work.
What are funnels? For certain goal pages, there is a set route of pages that users must go through to get to your goal page. This path is known as a funnel process, and by tracking people’s progress through a funnel, you can see where there are problems and where people are leaving the process.