There is a difference between combining things and fusing them. Both have to do with taking two things (at least) and creating one thing from the two sources. But there’s a difference in the end result depending on the process.
In a combination the two prior pieces remain distinguishable. The seam where the combination happened is also visible. The new thing feels more like a wrapper around the two sources than something new.
In a fusion the two prior pieces are indistinguishable from one another. The seams aren’t visible either. The new thing is actually completely new, not just a wrapper. This is because during the process of fusion both prior sources are fundamentally changed. A new tree is created from separate roots. Only people familiar with the prior sources and the historical context may be able to discern them while observing the new creation.
Many artists and designers attempt fusion but end up with a combination instead. If this is you, keep working. It isn’t easy. But the birth of a new form is a beautiful gift to give the world. Be encouraged. Your work lies before you.