First find where on your Android these are stored: Read from https://www.google.com/search?q=where+are+wallpaper+files+in+android&ie=utf-8&oe=utf-8
OK, now you'll need some file manager to go there and delete them.
So I installed some themes but I didnt like them so I uninstalled them. However the wallpapers from those themes are still in my phone and I cant find them anywhere except if I try to zoom out in my homescreen and press wallpapers, it lets me choose from: gallery, wallpaper or one of these wallpapers I got from the themes. Those wallpapers are rotating in my desktop like a slide show and I want to do it with different pictures so I want to get rid of those ones. My phone is Huawei Honor 7 lite

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