Microsoft’s digital assistant Cortana was first unveiled with Windows Phones and it is now included in all versions of Windows 10. The new feature lets you use the digital assistant to open and find files and save time spent navigating File Explorer or OneDrive. The feature is included in Cortana version 2.26701.0 or newer, which is currently available for download in the Windows Insider channels via the Microsoft Store. Once updated, you’ll be able to use Cortana to search for files by sharing parts of file names, author names, and file type.
Source: https://www.bleepingcomputer.com/news/microsoft/hands-on-with-cortanas-new-file-finder-feature-on-windows-10/