What strategies are there for finding literature for a literature survey when the terminology used is diverse?
I find searches based on keywords to be quite limited. You can play around with various keywords and see how far you get, but this only helps to get a first cut.

To deepen your search, use a snowball and reverse snowball procedure. This should get you around the problem that authors use different terminology. Be aware, however, that this may introduce some selection bias that you need to hedge against.

One way to reduce the bias and to broaden (rather than deepen) the search in addition to starting with diverse keywords is to ask around. You can just asks your colleagues but you can also get as formal as you want and conduct expert interviews or even surveys.