Fabric stores with non-plastic merchandise?

Hello, I'm trying to avoid having to make a habit out of ordering fabrics from other countries, and buy locally instead. All I've found so far are a ton of plastics, and some ridiculously overpriced (3 + times the value "designer" fabrics, whatever that means).

I'm also having unbelievable trouble finding a local that knows the Bulgarian word for "cotton canvas".

Please help me find an e-shop or physical store in Sofia, with a healthy selection of normal fabrics, if you can.

Thanks.