You can create the url by passing appropriate attributes :
<%=link_to 'Something Awesome', "/products/#{store}/#{destination}/#{category}"%>
I'm not sure what your use case is and how you plan to pass those parameters in the url.
But, you might want to create a form_tag instead for it's a much cleaner solution.
<%form_tag your_awesome_action_path do |f|%>
<%=text_field_tag :store%>
<%=text_field_tag :destination%>
<%=text_field_tag :category%>
<%=submit_tag 'Submit'%>
<%end%>
where, your_awesome_url is path to the controller action that will process the form.
you'll need an action your_awesome_action in the products controller and a corresponding route in routes.rb :
match 'your_awesome_action' => 'products#your_awesome_action'.