Anytune has Search and Filter capabilities.
Use Search rather than filter to find something you are not sure where it is, and use filter to narrow down the elements of the current list.
Search will search everything and everywhere. Search looks your music library and at songs imported directly into Anytune. Search looks at all strings including; Title, Artist, Album, and Playlist.
Scroll to the top of the list or tap the in the alpha index to reveal the Search box. The Search box is available on all lists within Anytune.
Filter will refine the current list displaying only the elements that contain the text entered in the filter box.
The Filter box is at the bottom of the list.