+ adds a new blank text note, pencil adds a drawing/handwritten note, picture allows you to take a image with the camera (or load one from internal memory or sd card(s)) as a note.

inputting some text and tapping the magnifier searches all text notes (and likely titles on the other two) for a match.

with a blank search you bring all your notes black after a search.

x will remove the note your currently loooking at.

and i have never seen any problem with saved notes, as long as they have some kind of content.