Thank you for the details, I have found a few configuration issues.
The index table engine was not enabled, therefore the titles were not searching for. Now it will return the correct results: https://i.imgur.com/F0dTt37.png
After the change I have also tested the speed of the search, which is now much faster, see this video: https://youtu.be/9oNZOpqg5zs
The response time is between 2-3 seconds, mostly around 2, which is still 3-5 times faster than your average site loading performance (with cache!!), see this test:
– Screenshot: https://i.imgur.com/T48rsAL.png
– Test link: https://tools.pingdom.com/#!/cd7Qxr/http://zas-store.com/
I believe the ajax response is still way above the expected load time. It should be okay now.
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