A fairly fresh installation of Magento 2.1.7. 1.9.3.x database migrated over. Everything was working fine, the search worked, until sometime today when it just stopped. The last thing I remember doing was adding the first new product into the Default attribute set (whereas all the other products use migrated_normal_product attribute set. Soon after doing that, search stopped working entirely.
It doesn't find anything, not with SKU, not with the product name. I've tried reindexing and clearing the cache, but to no avail.
Advanced Search can find the products just fine, but not the regular one.