How to recover files deleted in iTunes Mac version?

Recently I deleted some files in iPhone via a connected iTunes on Mac

Among them are some voice memo files listed in SONGs

Even though it does not make sure to recognize them as songs.

Later to find they do disappear from the voice memo apps both of iOS and Mac version!!

And there's no entry that said "Recently deleted" at all to recover them.

This is a great headache I have to say

for I barely find any trash in iTunes app.

Neither do they end up in Mac trash

Don't find any clue on iCloud either to seek if any previous voice memo backup

Please help dears, the memos are so important and hard to remember exactly..

You may create a test voice memo and repeat my steps, to see if you get same troubles.