Recently opened files can be seen in
Using RegRipper (https://github.com/keydet89/RegRipper2.8) you can verify this with the following:
rip.pl -r c:\Users\<username>\NTUSER.DAT -p recentdocs > rip-recent-docs-resultst.txt
This needs to be done on a copy of the DAT-file or from a mounted image, as the file cannot be accessed while running.
You can use the same tool to see what recent searches have been done from the Start menu:
rip.pl -r c:\Users\<username>\NTUSER.DAT -p wordwheelquery > rip-recent-start-searches-resultst.txt