It's in Russian. Search results in English won't show up. Edit: My bad. I was confused with the layout.

It's a desktop client for soulseek: https://github.com/Nicotine-Plus/nicotine-plus

Install, login/register, share your data then search. Filter the results by file format, sort by download speed etc. Soulseek is a very old file sharing platform, work the same way since 2001. A lot of peers don't allow downloading from them if you don't share anything.

For Android I found SeekerAndroid, never used it.

for Android there is a client named seeker. you need to create an account (mainly just a username and password) after that its pretty much setup. You can search for the song dat you want, download it and if possible also seed/share it with other persons :)