Hi there !
First of all no worries for the picture in French, it's actually a french forum here 😉
From what I understand, you deleted songs you bought on the iTunes Store from your playlist, or even your iPod touch, and want to retrieve them ?
If that's the case, you can check that on the exact page you sent, actually : click on "Autre" at the bottom right when you open the iTunes Store app on your iPod touch, then choose "Achats" > "Musique".
From there, you can search for all the songs you bought with your Apple ID. You have 2 options there : "Tout" or "Absents de l'iPod".
When you select a song, if it is indeed absent from your device, you'll have a little cloud next to it with an arrow inside ( ) that you can click on to download it again.
Otherwise, you'll have "Téléchargé" next to it instead, which means the song is still on your device and you can find it easily on the Music app, by typing the title of the song there : click on "Recherche" at the bottom right.
Let me know if it works !
Cheers