How advance search behaves. Because when I set filters and click apply it will not show any knowledge articles in the surface. We have to type some string in search bar and click enter then only it shows search results. Is this standard behavior?
Yes, that's expected behavior.
You're applying filters to be used on search results to narrow down what you see. If you don't type anything and click enter, the component will not search or return any results to filter which is why you see nothing.