How do I remove white residue from a brown bath,vinegar,and usual bathroom products not working?

live in FranceHow do I remove white residue from a brown bath,vinegar,and usual bathroom products not working?
you could also try...easy off bam. it is a grime and lime remover. it works on anything!How do I remove white residue from a brown bath,vinegar,and usual bathroom products not working?
try ''clr''