Thanks, checking on Spotlight was informative. According to Box, the Spotlight and Finder searches do NOT index Box files, even ones that are set Available Offline, i.e., a copy exists on the local filesystem. Box users have requested a fix, but nothing (yet) from Box. https://community.box.com/t5/Box-Drive-Known-Issues-and/Mac-Specific-Known-Issues-for-Box-Drive/ta-p/37353