when using control +F on Gnome using thunar i do see a search box it could be an issue with the keyboard shortcut mapping in the Desktop Environment. I tested this on a fresh install of 20.04 LTS version of Ubuntu Linux OS.
when using control +F on Gnome using thunar i do see a search box it could be an issue with the keyboard shortcut mapping in the Desktop Environment. I tested this on a fresh install of 20.04 LTS version of Ubuntu Linux OS.