You can view - but *not* move - multiple axis at the same time in the *curve editor*. This is because adjusting a curve usually only makes sense in 1 axis at a time. However if you want to adjust the timing/position of multiple keys at once you can do so in the Dope Sheet. I tend to use the Split view, enabled with the buttons on the right of the curve editor/timeline, which gives you both views to easily adjust what you need to. In the Dope Sheet view you can select as many keyframes as you want using drag-select or shift-select and then move them back or forward in the timeline together to "retime" things.
- Oshyan
