"Search your computer" button

Sorry, but I don’t understand. I cannot get to visualize any “search your computer” tip. On latest Ubuntu (called Bionic, version 18.04) I have in the top corner a label named “Activities”, which does not have any tooltip, and at the bottom left corner a grid icon, with tooltip “Show applications”

The super key (the one on the keyboard with windows logo, in most of the keyboards) shows the same view Activities button shows, but of course there is no tooltip

I wonder if you are referring to the text area in the middle of the screen , but again is not “search your computer”