Hi!
Thank you very much for all the details, it helps a lot 🙂
Okay, one issue was, that by default single character words are ignored by the search for better accuracy. The other issue was the keyword logic. By default word beginning and endings are also considered as matches – so anything containing the entered keywords was a potential match.
According to your needs, I made the following changes: https://i.imgur.com/djVSUYg.png
There is still a chance that some unwanted results will appear – as each word is compared against each field – and for example if the “8” is contained within any other selected fields.
I am sure however, that it should give you much more strict and accurate results now.