If you are not familiar with graph mode, read the tutorial.
If you are familiar with graph mode, maybe this tip be a little obvious, sorry.
Let's pretend you have an arrow which fall nailed on the ground. You have the arrow falling and the wiggle movement when its nailed.

Now, let's pretend you need several arrows which must fall at different places and times.

Normally, what I did was duplicate the arrow several times, put each one inside a group layer and translate each group layer to the new positions.
That's a good way, but if you want to keep your project simple, or if you have masks or complex hierarchies, to create a new group layer becomes a problem.
So, here is where graph mode becomes unexpectedly useful.
In normal timeline, you can move the keyframes and change the time in which each arrow will fall, but not where they will.
But if you activate the graph mode, you can modify the position of all the layer translation keyframes at the same time. just select all and move them up or down. So you can make that each arrow fall in different position, maintaining the animation and without creating any group.
Remember that in graph mode, the keyframe will be separated in 3: one for X, one for Y and one for Z axis, so you will have to choose which you want to use.