OPTION A:
Step 1: Do your search.
Step 2: Click on an image you potentially like.
Step 3: Choose “Search Tools” from upper right of menu.
… then you’ll see a drop down of a few menu choices including
“Any Time”, “All Results”, “Any Size”, “Any Color”, etc. appear!
Step 4: Choose “Any Size” and you’ll be able to get a larger format up to 2 or 4 MB.
OPTION B: Alternatively you can click on am image you like…
