My flooring gets stained easily.

The use of adhesive and cement during application produces residue on the surface which is not visible to the naked eye. This residue creates a highly-absorbent film on top of the ceramic tile and, over time, this will become much more difficult to clean.

It should be cleaned with HG Acid (available at DIY shops such as AKI, Maxmat or Leroy Merlin) or DETERDEK from FILA (sold by construction materials suppliers) in the concentrations recommended by the manufacturers.