When searching for a mod with a version selected and then by last released file it'll show mods that HAVE that version, but not necessarily the mod's last update WAS that version.
ex. I want to see the most recently updated 1.8.9 mods. I search and click on a mod only to find that it has an update for 1.9, not 1.8.9.
After a few times this becomes quite irksome. I hope this can be resolved in a future update to the website. I won't even start with trying this on the launcher. I stopped using it after the "pretty UI" update.