Back from the days when I used Squeak there was a nice tool called "Algernon" which was a simple "type in search" tool. I used it very often.
Later in Pharo days such a tool was missing - but after a while the "Spotter" tool for Pharo was provided by the GT team based on the same idea.
The nice thing is that now also the Algernon code was updated for latest Squeak in a project called "Algernon-Launcher".
BTW: Spotter does not allow to evaluate the given text as expressions, but the tool is extendable and maybe should provide this Algernon feature by default as well.