investigating fish broth

We have been trying to make good fish-based broth at home cheaply. The first picture is noodle in a broth made with the juice from mussels. Second is the "leftover" mussels stirred fried with some asparagus. Last one is a broth made with fish bones. The mussel broth was heavenly but the yield was little. The broth based on fish bones is a bit disappointing, probably the cheap bones we can get from supermarkets ain't the small and flavorful ones we are used to in HK...