I am a student .and I am living in sri lanka.my problem is when I pass stools sometimes the blood too comes.I feel very difficult when passing stools at that time.sometomes it swells .if you don't mind please give me an answer that what type of disease I am facing it.

Sounds like constipation... but if its more you'd have to have a doctor actually see you because we can't diagnose someone with few details over the internet. Particularly if this has been going on for some time... or if thre is more than a trace of blood. Though any blood at all is not a nomal situation.

Bleeding while defecating can be caused by many different things. It could be that you're constipated and you're tearing your rectum when you're trying to eliminate. It could be that you have hemorrhoids, it could be cancer. There are literally hundreds of things this could be, none of which we can diagnose online.

You need to see a doctor about this. If you're having problems passing stool, try eating more fiber, drink at least 8 glasses of water a day, stay away from coffee and teas they dehydrate you, as well as colas. Eat healthy foods, lots of ruffage. If this is because of constipation, making your stools easier to pass should help with the bleeding, but no matter what, you have to talk to a doctor about this so they can check if this is something more serious.