Alright, so.. I messed around with it, here's what I got for advice. It only gives you five selections to pick from and that sucks lol If the title of the song is unique enough, it'll show up for sure. This means either made up names or specific phrases.
For example, I have a track called "Moonflower (2017)", I thought it was a unique enough title to just put "Moonflower", nope. I looked further into it and searched the year as well and found it like that. I have another track called "Memories aren't enough." and that showed up for me. If you have tracks that use a single-word title, it'll be harder to find there. I found that it's super dependent on what you type in. If it still gets lost in a sea of Soundcloud tracks, try putting your username before the title of the track you wanna use.
If it still gets lost even then, try using the link to the track and cutting the part after Soundcloud in it. For example, (https://soundcloud.com/ar-ninetysix-1/03-memories-arent-enough) gives you nothing, but if you cut it like this (ar-ninetysix-1/03-memories-arent-enough) it should work. Anything past that, and uh.. yeah, give it a different title and try these steps again?