HTC Desire SV User Manual page 21

21 Your first week with your new phone
Two-finger swipe
Pinch the screen to zoom out of the picture or
text.
In some apps that have sorting, like Mail or People, swipe
up or down using two fingers to scroll the screen. The
screen displays the sorting order, and you can easily scroll
to the information you want.
In the Notifications panel, swipe down with two fingers on
expandable notifications to see more information like email
previews or calendar events.