For example you are working on items module and you have a index page like listing all items with pagination. also you did give search function on items name. I have a bellow query string when i search something and i want to pass that query string on all pagination link.
<strong class="example">Query String URL:</strong>
But where is problem. when you search any for example "tes" and get the result but when you click on next page you can't filter on name as you did "tes". so at that time we have to appends that query string on pagina.....