Decompiling a 16-bit dos application
===

I have a very old application which I bought about 15-years ago,it consists of 5 .exe files used for storing patients' profiles and information. the problem is that this application was programmed to work on a specific computer. and because I have little knowledge about cracking, I tried to disassemble it using win32dasm but there were no information about string references, tried Hiew to replace je by jne and after many, many tries one of the executables worked, but I failed to patch the other files
Is there any way I can find the exact jump and patch it?
thanks ;)