Yellow stains on clothes

[ElzaAnn]

Last day while I was cleaning my cupboard,  I found that some of my favorite fabrics have some yellow stains on it. I wonder what might be the reason for it. I have seen some fabric cleaning tips online for removing the stains using vinegar, http://www.sunrise-cleaning.com/blog/cle...ar-stains/, and  I had done this previously to remove a coffee stain on my curtains and it had worked. But I am little afraid to pour vinegar on my fabrics because this fabric is costly one, and the material is different from the curtain and I have read that the stain of the vinegar might not go from the fabrics. Can I use the same vinegar + baking soda procedures for removing the yellow stains? Can I get your suggestions regarding this? I want my fabrics without any stain.