what is ferro liquid?

Question

it makes magnetic field of magnet more strong

Answer 1

He is my (educated) guess. Since ferro means Iron like, or now-a-days anything that can be made into a magnet or will be attached to a magnet (ferromagnetic).

To make a ferromagnetic material a magnet, or a stronger magnet, you would heat it, even liquefy it, thus allowing more electrons (domains) to align. The more that align the stronger the magnetism.

phew!