I lost all my files after restart iMac. Help

When I use the browser, "aww snap" is displayed and a restart is recommended.

After restarting I re-login my Apple ID. when finished, I open my finder to check my data.

and it turns out that the data no longer exists.

my application is also all gone

however, when I type a file name in the search bar, it will display data according to keywords.

The data seems to still be there, but I don't know where to look. because at first I put it on the desktop. and now my desktop is empty

Please help me. many important files there