[xsl] How to make a request to a same file to generate different content

[IceT <icetbr@xxxxxxxxxxxx>]

I have a menu bar with a few links. When I click on one of them, a xml 
file is called with its own stylesheet. Then appears a submenu relative 
to that menu item. When one os those subMenuItens are clicked, the same 
xml file is used to generate a different output:

College members (url = members.xml)
     old members (url = members.xml)
     new members (url = members.xml)
College buildings (url = buildings .xml)

How can I do this? Using Cocoon I can create an elaborated request and 
then use it to select a suitable pipeline:

College members (url = members.xml)
     old members (url = members.xml:old)
     new members (url = members.xml:new)
College buildings (url = buildings .xml)

How would I accomplish this using only xml/xsl ?

Thanks