Hi @Kristy Monahan ,
Welcome to Q&A Forum!
You can type the SharePoint site's name in the "Search in SharePoint" box to search site.
If you can't search these sites, please perform the following troubleshooting:
1.Make sure these sites still exist, you can contact the Global Administrator to check
2.Make sure you have permission to the site. For example, you cannot access this site, then this site will not be searched.
Thanks,
Echo Du
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