This Pochwa icon is made in Material Design style developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 4,300 icons, all in the same style and quality.
The icon is shaped like two parentheses facing each other but not fully touching. Inside directly in the middle are another set of parentheses but this time they fully touch. Inside of that one is another set but they aren't in the middle, they are towards the bottom.