An unexplainable feeling

In this world, there are many unexplainable incidents

He developed an unexplainable appetite for pumpkin pie.

You had just become aware... of a curious, unexplainable, epidemic mass hysteria.

I, your Wizard per ardua ad alta am about to embark upon a hazardous and technically unexplainable journey into the outer stratosphere!

He was still searching for a way to explain to others what he feared was unexplainable, the path to the enlightenment he himself had experienced.

Likewise, as in Hong Kong, an amnesty could be granted, conditional on financial disclosure and a fine for unexplainable wealth, for all but the most egregious behavior, thereby leaving the past behind.