hn.algolia.com can't do "or" so just the normal stuff for search would be a good start.
https://hn.algolia.com/helpThe date chooser on hn.algolia.com is also broken but a very handy setting.
And I just saw why search always brings up wrong stuff "typo-tolerance" is default on - https://hn.algolia.com/settings
I have been to the settings, but it's a good example of why defaults matter and on-screen really helps people.
And extra crazy with "typo-tolerance" ON, "optimized" and "optimised" are very different results. Which is technically true, that is not a typo, that's grammatical.
Filter by author is important as people use that to search their own stuff.