Not really. Its basically an annoying call that says 
if there are no clauses, return nil
if there is just one, return that clause
else return {"$and" => clauses}

Only thing I can break down here is something like

make_id_clauses
make_date_clauses
make_type_clauses
make_severtiy_clauses
and then have that ugly switch statement... Would that be ok for you ?