Thanks for the suggestion, Jason.
I understand what you’re trying to achieve and I think BrewwQL being available here might be the right answer. BrewwQL has proper support for AND vs OR searches.
The general convention in search systems (i.e. everyone knows how to use Google) is that adding more words will narrow down the results further. This essentially makes all terms required. I follow the premise of your logic of + having a special meaning in comparison to & but this just isn’t “normal”. To ensure our user interface remains as intuitive as possible, we need to stick to the conventions that people understand. Giving & and + a special meaning, would, I feel, cause most people confusion (even though it would make sense to you).
We’ve already got a thread for Allow filtering the all products list and available products report with BrewwQL, so could you give that a vote and we can look to add BrewwQL to the “All products” list?