For whatever reason any sort of configuration of the search function like and or or doesn’t give the proper results in search results box.
For example, I’ve tried both AND / OR functionality, while setting up product name as top ranking priority, the products I’ve tested have a wide array of fitting search terms and still the search function shows completely unrelated products:
20kg product-name some-more-details-here ← the tested product
searching for it in the search box:
[20 kg] no hits, unrelated products at top of search results
[20 kg with few letters from the product name] same thing, it gets a little accurate but with every extra letter it shows completely unrelated results
[20 kg product-name some-more details-here] ← full product name, no hits, on OR functionality it appears somewhere in the bottom of the list.
Having the whole search ranking stripped down to such basic functionality, it looks like shopware has some issue matching search terms / ranking factors to proper products.