You are searching all available Racket packages, including those that you may not have installed locally. Therefore, you may need to install a package to use the results shown below. Getting Started with Packages guides you through this process. If you want to re-run your search with local results only, press F1 in DrRacket or run raco docs on the command line.
You are searching only your locally installed Racket packages. More results may be available by using the global search that inspects all available packages. You may wish to repeat your search globally.