At the top of the screen, click the People tab: In the Find box, type up to four letters of the person's last name. Don't type more than four letters of the last name; the person ID is the first four letters of the last name and then the first two letters of the first name. Thus, for Lucy Pevensie, you'd get a match if you typed 'Peve' but not if you typed 'Peven' (because the search is actually looking for PeveLu). When typing in the Find box, Chronicle automatically searches as soon as you stop typing.
To search by other information: Click the Search button in the tool bar to indicate what you want to search by, and then enter the text to search for.