Maybe it's a paintbrush's paint. Or it's some dirt which your shoe might have caused.If you have a dog it might be the dog.
Use Resolve, and then rub it in and then vacuum over it.
Use VANISH, the stain-remover. It is very effective.
You would probably have to get a wet towel and wash it out. If it doesn't work, try using soap.
One of the best stain lifters for carpet is baking soda, not only does it lift some of those stains out, but it will also deodorize it. If the stains are too old and set in, another solution would be renting a carpet cleaning company to do all your floors.
sorry but there is no way to remove bleach stains. reason is that bleach causes decoloration and not a stain.
stains are on carpets because of people walking on them
You can use hydrogen peroxide to remove pet stains from white carpets. Simply mix peroxide with water and pat onto the stain. This does not work for colored carpets.
Hoover Steam Vac is the best steam vacuum for dirty carpets and cleans tough stains.
capet cleaner
Try Resolve carpet cleaner, that worked to get most all of the stains out of my carpet when i moved.
Use Resolve, and then rub it in and then vacuum over it.
Please go onto: www.google.com ASK: Household tips for stains in carpets
Use VANISH, the stain-remover. It is very effective.
You can put rugs on carpets so your carpets wont be stained. There is nothing you can actually put on a carpet other than a rug to prevent staining, you can only deal with a stain once it has happened.
Uncleanliness to start with.
Normally the carpets on your floors do not contain lead.
Most new carpets come with a factory-applied protectant but this wears off over time. Reapplying a protectant on your carpets can help oppose stains and soiling, so your carpets will stay cleaner longer. Another reason protectant is a smart investment is that it slows the aging and wearing procedure and can extend the life of your carpets.