Is there greater explanatory power in laws governing things rather than being descriptive?
Of course, and the body of the question seems to recognize this. The latter kind of law provides for prediction, but no real explanation. The former provides explanation, albeit a somewhat unsatisfactory one, to wit: it is a characteristic of the universe, as it is today, that things behave according to such-and-such law. Of course, that does beg the metaphysical question of why the universe has that characteristic.
The question is moot, however, because we have no tools for discovering such governing natural laws. Our best tools and methods for exploring how the natural world works -- scientific ones -- are fundamentally built for and around interpreting our observations, thus they produce descriptive principles.
Scientists do generally work under the assumption that the perceived regularities of our universe are indeed grounded in fundamental natural characteristics. They do generally suppose that the scientific method is effective for discovering better and better approximations to those underlying natural laws. That seems to have been working well for centuries. But scientific "laws" are a predictive codification of observations, not to be confused with the true underlying characteristics of the natural universe. If ever we do come up with a scientific law that happens to exactly match a natural law, we have no way to recognize that we have done so.
Sometimes, a scientist will express that such and such scientific law / principle explains a given observation. This is pretty common, in fact. But such a claim should be taken as code for the observation being consistent with said law / principle, or else the claim should be taken as contingent on the law / principle being a close enough approximation to a true characteristic of the natural universe, or both. And that's ok.
