The locator is a central component inside Qt Creator. It allows developers to navigate fast to specific locations inside the source code or inside the help. To open the locator press
A pop-up is coming from the bottom left and shows a list of options. If you just search a file inside your project just hit the first letter from the file name. The locator also accepts wild-cards, so
\*main.qml will also work. Otherwise, you can also prefix your search to search for the specific content type.
Please try it out. For example to open the help for the QML element Rectangle open the locator and type
? rectangle. While you type the locator will update the suggestions until you found the reference you are looking for.