Songs and artists on Apple Music, but not available to buy on iTunes?

I do not have a mac, or an iPhone, I just have my iPod touch and iTunes on my laptop, so maybe that is part of it but I don't think it is. But there is at least 1 artist who I have searched on iTunes for them and their songs, and on the iTunes store, nothing shows up, but when i generally search chrome and add the sone mane, artist and "iTunes" at the end of the search I get the page for that song and artist on the Apple Musc page and can play the demo, but there is no way for me to purchase the song or album. If I click on the three dots at the end the only option it gives me is "share". nothing else. If it is a country restriction thing, that I understand. I live in Canada, there are a few Doctor Who things I've looked for on the iTunes store, but they are only available on the UK version. That I get, and iTunes tells me that, because when I look that stuff up, there is an "open in iTunes" button, and I press it and get the "not available in your country" or " not available on your version of iTunes" window. That I get, but I don't think that is the case with this, because there is no "open in iTunes button, just ads to subscribe to Apple music, which I don't want to do. So why is nothing coming up when I search for this artist on iTunes but they and all their stuff shows up when I search them on Apple Music??