How are you browsing your Amazon content? I see search bars on the 'All Content' [1] page, and also on each individual page, like my movies and shows [2].
Though it seems like the interface is pretty rubbish in the Prime Video section [3], so maybe that's where you're looking?
Roku based TVs and their mobile app. And the website - #3 in your list above. Never seen those other two links, and they don't show up when you're trying to watch things on your tv.
Though it seems like the interface is pretty rubbish in the Prime Video section [3], so maybe that's where you're looking?
[1] https://www.amazon.com/hz/mycd/digital-console/contentlist/a... [2] https://www.amazon.com/hz/mycd/digital-console/contentlist/v... [3] https://www.amazon.com/gp/video/mystuff/library