Add multiple filter example to about page

views/about.html

@@ -16,6 +16,7 @@
       <div class="content">
         <p>You can search for Tor nodes by entering part of the nickname, hash or IP address into the search bar. Filters are also accepted, they can be used by specifying an Onionoo parameter and value separated by a colon, e.g <code>country:gb</code>, <code>contact:luke</code> or <code>flag:Fast</code>.</p>
         <p>To search for nodes in Great Britain that contain the string "jug" in their nickname you would search for <code>jug country:gb</code>.</p>
+        <p>You can also combine multiple filters, for example: <code>country:gb contact:luke</code>.
         <p><a target="_blank" href="//onionoo.torproject.org/protocol.html#methods">View all Onionoo parameters.</a>
       </div>
     </section>