There were some rusted screws in my washing machine. The cloths touched with the rusted screws and got stained. I am unable to remove these stains. I even tried bleach and soap but that just lightened the stains. Any suggestions?
First off, don't use bleach; bleach works by oxidizing the stain, which tends to make rust stains worse. There's a commercial product called "Iron Out" that uses a thiocyanate to very effectively remove rust stains, but you can do the same with oxalic acid, if you have access to that and not to the commercial product.
Oxalic acid can be obtained from rhubarb leaves (it's the toxic component in those leaves, so avoid ingesting it and wear gloves while preparing and using the solution). If you have that plant in your garden, though, you'll want to take precautions to avoid replacing the rust stain with a green chlorophyll stain if you use rhubarb as a rust stain remover.
I googled and found this answer:
Lay the clothing or fabric out on an old towel and pour a small amount of white vinegar directly on the stain – or rub a cut lemon half on the stain.
Saturate it thoroughly, then blot it with a clean white towel.