The Quick Add Tool
The Quick Add tool is the fastest way to add UI controls to your wireframes. To use quick add, click inside the quick add input box (or press / or + to enter it).
Type a few letters from the name of a UI control or icon and Quick Add will show you a list of suggestions. Use your mouse or arrow keys to scroll down the list and click or press ENTER to add the control or icon on the canvas. You can also use SHIFT+ENTER to place the control where your mouse cursor is on the canvas.
For example, typing "bu" shows a list containing "Button", "Button Bar", "Help Button", "Radio Button" and "Round Button". Typing "hel", on the other hand, only returns "Help Button". Pressing the ESC key makes the list disappear.
Tip: As you become familiar with quick add, you can hide the UI Library and only use quick add to add UI elements to your wireframes. This maximizes both your canvas area and your speed.