Its frustrating not beeing able to quickly inable or disable the filter feature without getting in to laborious button pushing ,
Suggestion, make the filter a button that lights up when enabled or disabled , a one quick touch toggles this function on or off but is you need to change the filter criteria you either long press or double tap on the button so then you change your optional needs., otherwise you are continually button pushing so the search works correctly,
Search should always search the entire song library otherwise you can get caught with your pants down if you havent selected all songs this is so unnecessary and confusing.