Settings Search not working in Windows 11/10
First of all open your Computer folder, right-click on your system Drive which is C, and select Properties. Ensure that the Allow files on this drive to have contents indexed in addition to file properties box is checked. If not, select it and then select Apply changes to subfolders and files.
Now, open the following folder location: Here, right-click on the Indexed folder, and select Properties. Next, click on the Advanced button and check the Allow files in this folder to have indexed in addition to file properties setting. If it is already checked, uncheck it and click OK. Then again check it and click OK > Apply and exit.
Restart your computer and see if it has helped. If this does not help, you may want to run System File Checker, repair System Image or rebuild Search Index and see if that helps you. See this post if Cortana and Taskbar Search is not working.