A careful study of the abstract shapes and lines used here by the artist will help you to discover the fish, from the imaginative mind of Miro.
Miro concentrates on the eye and scales for detail on the fish, allowing the viewer to recognise what is meant, and then constructing the rest of the image in their own mind.
One commonly quoted comment from Miro, which is particularly apt for this particular painting was "...In my opinion, mastering freedom means mastering simplicity. Then, at most, a line, a color, is enough to make the picture..."
This simplicity of colour and line can be seen through out his career, as well as in the work of other famous modern artists from the 20th century, such as Piet Mondrian, Wassily Kandinsky, Mark Rothko, Paul Klee and Jackson Pollock.
The Singing Fish, both in it's simplicity and also the subject matter, has clear influences from prehistoric cave paintings which Miro is known to have studied and sought ideas from early on in his career.
The bold colours and child-like capture of objects is typical of abstract art in general and more of these ideals can be found in the work of those artists mentioned here, as well as Pablo Picasso too.