advanced search form generates lots of blank query parameters

[fbstj]

clicking the search button without changing the form will go to /adv_search/?query=&date_from=2003-12-05&date_to=2018-04-26&speaker=&ordering=rank and will respond with EVERY entry in the database

it would be nice if the empty fields could be stripped out (they are on page turns... though it seems that the date range isn't as it isn't empty)