The Asset library is where all your assets are stored ready for use on your drawings.
Assets can be reordered in the asset library to make the most common ones become available at the top of the list.
Pin Assets
By right clicking the asset you can "Pin to Favourites" which will bring the asset to the top of your list.
As an example, I have pinned 5 assets (highlighted in yellow).
Unpin Assets
To unpin an asset, simply right-click again and select "Remove from Favourites".
Reorder Pinned Assets
For assets pinned to the top, you can simply hold-and-drag to change the order they appear in.