Detect copy/paste done performed in guest OS running in a Virtual Machine on macOS host I have copied certain text in CentOS running as a guest in Virtual Machine which in turn is running on macOS host.

Guest: Virtual Machine - Centos v7.5 
Host: macOS - High Sierra v10.13/ Windows 10.

The functionality needed is to  detect a txt copy operation from 
a file inside the Virtual Machine to paste operation on macOS where presumably this data would then be pasted to a file/website/e-mail. I was just wondering if you can somehow know that and if you can give me an example of such "tool" that can record/spy on the host actions. 

Is it possible to detect that some text was copied/moved to a file/e-mail/website in host OS (macOS)?
No, it is not in general possible to detect whether a file or a text message has been copied from a virtual machine to a Windows or Mac computer.

An adversary could do this undetected even through such means as OCR'ing (optical character recognition) the text on the virtual display. The virtual machine cannot in any way detect whether it is a normal human being looking at the display, or it is a program that is silently recognising and copying text.

Files can also be copied by the host machine accessing the underlying disk storage directly without giving the guest virtual machine any way of detecting that the file system has been accessed, and file contents copied.