My memory card which comprises many vital things was stolen by a guy....though i didn't see him when he took it,but i knew he was the one who took it...what can i do?

It depends. Is he bigger physically? Are you into violence? Or would you rather let things go? How sure are you that he took it? Do you believe in negative prayers?
Logic indicates that you confront him about it. Dont accuse him of stealing it, just pointedly let him know that it is missing. Tell him you have valuable information on it and you'll be really pissed if its not found. Tell him to 'help' you search for it. That will give him the option of conjuring it out of somewhere and saying he 'found' it. If he proves stubborn however, you either let it go to catch him another time or you get physical and search thru his things.
Those are the options I can think of.

Royver: It depends. Is he bigger physically? Are you into violence? Or would you rather let things go? How sure are you that he took it? Do you believe in negative prayers?
Logic indicates that you confront him about it. Dont accuse him of stealing it, just pointedly let him know that it is missing. Tell him you have valuable information on it and you'll be really pissed if its not found. Tell him to 'help' you search for it. That will give him the option of conjuring it out of somewhere and saying he 'found' it. If he proves stubborn however, you either let it go to catch him another time or you get physical and search thru his things.
Those are the options I can think of.

.thank you very much my brother,i understand everything you said,i decided to let it go,but some people who know the value of what the memory card contains are ready to fight for it with their lives coz the guy is a cultist....i'm confused and the only thing he can use on it is songs,even not all of it coz i have about 650 songs on it.....i love your advise bro

Calculusf(x):
.thank you very much my brother,i understand everything you said,i decided to let it go,but some people who know the value of what the memory card contains are ready to fight for it with their lives coz the guy is a cultist....i'm confused and the only thing he can use on it is songs,even not all of it coz i have about 650 songs on it.....i love your advise bro

he's a cultist? lol.......the first comment has said it all but its good u let it go cos nothing in that m.card is worth fighting for,just get a new one and move bro