texture variations with clouds for displacement modeling?

I’m attempting to model an old book (closed) and while I can use a texture for the pages I’m creating the edge of the page and applying the cloud image to a displacement to give it a worn look but the repetitiveness of the texture for each “page” object I create results in an object with no variation each time I create it.
is there a way to change the Cloud texture’s seed in Blender. I’m aware there are a few presets in the Basic dropdown menu and you can change the size but it does not look like I can change the seed.
Also what is the Nabla? It doesn’t appear to do anything when I change the value.