You can't do that in vi. Vim is from the Amiga, not Unix. In vi you have to say d?foo^M/bar^Mp, and though that's less keystrokes, it's harder because you don't have the continuous feedback of v mode or incremental search. Isearch isn't from Unix either; it's from ITS Emacs and wasn't in vim. It was Jef Raskin who did the research to justify centering it as a navigational method by quantitatively demonstrating its superiority to the mouse.
Of course if you don't have Vim in your brain none of this text will make any sense to you; it's almost like reading a list of (x,y) coordinates if mouse clicks. So you won't have any idea about the UI feedback I'm talking about, and you're likely to make clueless sarcastic comments like the one I'm responding to. But you can easily remedy that ignorance by running Vim or Emacs on an appropriate file and typing the recommended keystroke sequences.