Hello Halim,
You can find an images of Corculum cardissa on Guido Pope's web site :
http://www.conchology.uunethost.be/EN/cyber.html
I'm also a beginner and I use to go to Malaysia on summer so it can
happen that I have some publications you might be interested in, let
me know ([log in to unmask]).
By the way you should have a look on Chan's website : http://www.molluscan.com
He's from Singapore and mainly interested in land snails but you can
also find images of marine snails :
http://www.molluscan.com/shellimages/
Kind regards,
Sophie