I know away u should be able to do to get the stains out. First spray the stains with carpet stain remover ,and yes carpet stain remover because it is stronger than clothing stain remover. Then soak it in a sink of really hot water. The hole thing needs to sit under the water. Than spray in some more carpet stain remover. Let that sit for about a hour. Then just put it through the wash ,and it should come out whiter than ever. I do this a lot when I get those really hard stains ,and it has always worked. I do this to my white clothes every so often to make them look more white agean.
U will not be disappointed. The method mabe sounds weard but it works really great. I had a white basketball jersey that my sister spilt red juice all over. So I did this for it ,and it worked great.