I am on haemodialysis since 5 years. Is it ok to take plavix (clopidogrel) with aspirin for my case? Even at dialysis day? Thanks

Probably.. There are specific indications to be on blood thinners like Aspirin and Plavix (clopidogrel) and only your doctor can advise you safely. Generally these medications are not held on dialysis days. Check with your nephrologist though.
Yes. Lots of dialysis patients take these drugs for atherosclerotic conditions to decrease the platelets from clumping together.