Hi there, @ibiza69,
I tried to replicate this on my test site but the search seems to be working okay on my end.
Did you notice the issue occurred after a core/themes/plugins updates or after any particular change?
There may be something else installed on the site that’s causing problems. Can you temporarily deactivate all plugins except Sensei to see if there’s a plugin conflict? The Health Check plugin helps you to do that in the Troubleshooting mode without disrupting the live site:
1) Install and activate the Health Check & Troubleshoot plugin from the Plugins page.
2) Enable the Troubleshooting Mode from this plugin and a default WordPress theme, and make sure only the Sensei Pro and Sensei LMS plugin is active. Here is how it should look:
Screencast Link:https://d.pr/v/qJSK8d
3) Check the live site and see if you can reproduce the issue.
4) If you can’t reproduce the issue and all works well, one of the plugins is causing the issue. Enable the other plugins, one by one, and check the search after every plugin enabling and see when the issue appears; do the same with the theme by enabling the theme you want to use. Please note that your site visitors will not notice all these actions, so there is nothing to worry about.
Let me know what you find out, and we’ll take it from there if necessary. Thanks!