My scenario: I have added a content search web part to a page and trying to return pages from the link "https://tenantname.sharepoint/sites/sitename/pages/foldername".
I have just created the "foldername" folder and reindex the site so that it shows up in the content query result box but unfortunately i see nothing.
Any clue why this simple task is not working.
In SharePoint online it takes at least 15 minutes, sometimes longer , before the content is indexed. However I would suggest that you verify the search using the Sharepoint search query tool in order to ensure where the issue is
You can use Security & Compliance Center to export the crawl log, check if the pages in the new folder are crawled.
Check the article about How to download or view SharePoint Online Search Crawl Logs using Security & Compliance Center
