Happy immich user here! I once took a cute photo of our baby
chewing on a whisk, and actually finding the correct photo in an unsorted, untagged huge pile of photos by simply searching for "whisk" was a mindblow experience! It is an amazingly powerful tool!
How does it compare to Google Photo search? I search things like 'whisk' with success regularly... though to be fair not as random as whisk, but things like "steering wheel"