i don't think there is a quick way to get things of differnt fields into the clipboard at mp3tag.
there may different workarounds:
you can create a Tool in mp3tag which opens google images in the browser with your dersired search terms
Custom Tools
there is a web sources script for google images (gives only preview of the selected image):
/t/11166/1
and a plug-in for image search (somehow difficult to operate):
/t/11341/1