I need answers on this please

I would firstly like to know what is your rights as a South African citizen to just be stopped in the street and being searched by a police officer without any documentation just saying that he has got a suspicion that I'm doing drugs which is not the case at all going through my pockets my wallet and everything and humiliating you in public I'm saying that he can do it we can search for if you want to but on the same Street people standing drinking alcohol and smoking **** so how can that be possible in this country the search innocent people but they leave all the people doing all the other crimes right in front of them this happened in brakpan then about 9:00 this morning