There are ~65,000,000,000 neutrinos from the sun passing through each square centimeter of your hands every second as you read this. There are no materials on Earth that can reliably stop any given neutrino. For that, one needs densities greater than those generally found in stellar cores.

Neutrino detectors work by maximizing dumb luck through being both very large and very, very clean (low radioactivity). The transmitter-detector systems work by sending oodles of very energetic neutrinos at a well-defined time and looking for a rare coincident flash in the detector.