unless I'm mistaken, there's nothing in SL to generate links like that
the link you show would have been created from a get request from a
search form
although there is nothing to stop you making these yourself - the
pattern is pretty straightforward
just
link_to "Your Link Text", "/activities/search?search[order]=&search
[created_by_id_equals]=30&search[hidden]=1"
of course, you'll want to make the url bit something dynamic