You can have teeth "sandblasted" to remove the white blotches and achieve a better colour, but you would probably need to be referred to a specialist for this via your dentist.
The white patches are usually caused by you having had a virus when your permanent teeth were developing and antibiotics being taken, or hypoplasia, where the enamel fails to form properly as the tooth develops.

There are some new products and treatments out right now specifically for this. It's still pretty new so I would see a dentist or two and see if anyone does anything for this problem.

I am not sure what the user above me is talking about with the "sand-blasting" The products I know of are all chemical. I use a "sand-blasting" technique for polishing stains off these but it doesn't remove white spots. So not sure what thats about but I don't think it's the route I would choose.

There are some new products and treatments out right now specifically for this. It's still pretty new so I would see a dentist or two and see if anyone does anything for this problem.

I am not sure what the user above me is talking about with the "sand-blasting" The products I know of are all chemical. I use a "sand-blasting" technique for polishing stains off these but it doesn't remove white spots. So not sure what thats about but I don't think it's the route I would choose.

The tooth can be etched with a specially formulated dental acid to take the outermost layer of enamel off, leaving a more even colour to the teeth. This is usually done at a dental hospital, not dental practice. It is not a perfect result but can be tried before veneers or crowns, as a composite layer often fails.

What is a dental "hospital?" I've never heard of that in all my years in the field. I assume you are not from the U.S by the way you spell color, "colour" so maybe it's something overseas. Sometimes the countries overseas are ahead of the U.S. with these new techniques b/c our FDA takes forever to approve things here.

There are offices that will etch the white spot, then apply MI paste to it to remineralize it. Not something I have personally done yet thought so idk how successful it is

Yup, I live in the UK, hence the differences with treatments. We are not necessarily ahead of you, I sometimes think things are approved more easily over here. Not always a good thing!