[closed] wireshark question?

I have made the following experiment in my LAN:

I had 4 computers in this experiment. I used Computer B to send data to Computer A and Computer C. The objective was to capture the data being sent to the printer (computer A) and to computer C by spoofing the mac address of both addresses (different vmware machines) (device manager -> network properties -> networkaddress) and by using wireshark and other software to capture the word documents being sent by these systems.

Experiments results: how ever... none of this worded... from that point i started using cain and abel (to capture the data between computer B and C and between the router and Computer A)... once again ... nothing appeared... later on i started using another software (York)... again nothing

Experiment prediction: I would be able to capture the word documents by spoofing the mac addresses of these systems

computer A: the printer

Computer B: the sender

computer C: the victim

computer D: the attacker

Computer D.1: vmware of computer C (in bridged mode)

About Computer A: Computer A is a xerox printer i have in my lan... it is receiving a word document from Computer B for printing

About Computer B: the sender is sending 15 documents in word (to a folder being shared) to computer C

About Computer C: Computer C is sharing a folder in the lan and he is receiving 15 word documents from computer B

About Computer D: Computer D is using computer D.1 to spoof addresses and to capture using cain and abel

capture wireshark content: https://www.youtube.com/watch?v=GwAxzXSssz8

York software: http://www.addictivetips.com/windows-tips/sniff-network-traffic-capture-files-images-web-sessions-with-york/

Cain and abel: http://www.oxid.it/cain.html

Why do they say: "curiosity killed the cat" and why not "the mousse was killed by the cat"?

Question: How do you spoof a machine (computer/printer) and capture its documents of these systems by using wireshark?

Best Regards.