To find files that do not have any owners or do not belong to any user in a Linux or Unix system, you can use the find command with the -nouser option.
For example, to find all files in the current directory and its subdirectories that do not have an owner, you can use the following command:
find . -nouser
This will search for all files in the current directory (.) and its subdirectories that do not have an owner specified.
You can also use the -uid option to search for files that are owned by a specific user ID. For example:
find . -uid 0
This will search for all files in the current directory (.) and its subdirectories that are owned by user ID 0 (typically the root user).
Keep in mind that the find command has many options for filtering the files it searches for, so you can fine-tune the search to meet your specific needs. For more information on the find command and its options, you can refer to the documentation or use the man command to view the manual pages.