Use the Search Navigator in Xcode
Whereas the Find command in Xcode works for locating an item in a file or class, you use the Search navigator (the third button from the left in the Project Navigator toolbar) to find items in your project or even frameworks.
You can use Shift+Command+F as a handy keyboard shortcut for the Find command in the Workspace menu item, which also opens the Search navigator pane.
In this figure, the app developer entered viewDidLoad in the Search field. The developer also clicked the magnifying glass in the Search field to display search options. (Clicking in the Find pop-up menu will also let you choose Replace to perform a global replace).
Note how the initial results of the search are displayed in the Search navigator; if you wanted to filter the Results list still further, you could enter text into the field at the bottom of the pane. Any items that don't match the text are removed from the Results list.
To go directly to where the search term appears in a file, click an entry under the file’s name in the Search navigator, as shown in the figure. The file appears in the editor pane on the right, open to the location where the search term appears.