Google Retro Clean. It worked well for me on yellowed fabrics, 30+ year old coffee and tea stains (on linen), cat urine that had been there so long it didn't smell anymore (EEEUUUWWW!), and it brightened the fabric without hurting it. The stuff is spendy, but works. You do need sun to make it work. Check to see what is said about rust and blood. Those two things I didn't have! Hope you find something that helps.