How to sell stocks that are back office (In Holdings)

I am new to zerodha
How to sell stocks that are back office (portfolio–>Holdings).

@Ravindra464 : the stocks are not in trading account mean the same are not traded or listed hence in portfolio /holding . this is my understanding . you have to look for unquoted share dealers (there are many if you google) who may buy .you can also name these scrip on this board itself so as to get quote from somebody.