What are some good graduate level books on applied mathematics which explain in-deep in-depth the general modern problem-solving methods of the real-world typical hard problems?

There is a lot of books on numerical methods, engineering math, but I do not know any good modern book, which emphasizes algorithmic complexity of the discussed problems.

What are some good graduate level books on applied mathematics which explain in-deep the general modern problem-solving methods of the real-world typical hard problems?

There is a lot of books on numerical methods, engineering math, but I do not know any good modern book, which emphasizes algorithmic complexity of the discussed problems.