Where to buy liquid to remove earwax?

My left ear is completely blocked with wax. Back in my home country, I could just get a liquid from the chemist, put a few drops in for a few minutes, and within a couple of days the wax would fall out on its own.

Here, I’ve checked local chemists but they don’t stock anything like that – just Q-tips and similar products, which most ENTs don’t recommend.

I’ve been using a Bebird at home to see the buildup, and it’s clear that some kind of wax-softening solution would really help. Does anyone know where I can find this kind of liquid in Japan? Thanks!