The only proper way to clean seats or carpets is to have them spray extracted! you can use spray cleaners or foams and they will get stains out but you are only pushing the dirt around within the cloth and you are not rinsing out the product - most of them cheap cans you buy from halfords contain a mild version of bleach - ( thats why they are so good at removing stains) like 1001 etc - if you can afford it get the seats cleaned properly - I dont know where you live but down in essex i used to charge around the 40 quid mark - thats for seats, carpet & head lining - Good luck!