I don't think CHS can stop other applications seeing new clips, but it has a feature to ignore clips coming from certain applications, if that's what you mean. Bring up the main window and go View -> Options and select the tab Capture Options. You then find a box labelled "Ignore these applications (just filename, each on separate line, e.g. notepad.exe)" and enter the names of the programs you want ignored. Mine contains, inter alia, keepass.exe, pins.exe, etc.