How to select data on a certain surface

Hello, I have a box, and inside the box, there is a spherical surface (The inner boundary). I applied pressure to the node on this surface

Can anyone help me with how to use the data filter to only see the data for the point on the inner boundary in the vtu file?
Here is my gmesh file, the surface is called my inner surface

New Text Document.txt (397 Bytes)

Here is the link of dropbox to download the vtu example