Perhaps you should try some spelling variations:
"descending colon" » "ascending colon", "descending chain", "descending coronary"
"descending motor" » "decoding motor", "descending control", "descending aortic"
"descending down" » "descending da", "descending pain", "descending sort"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("descending colon") OR ("descending down"))) OR ("descending motor")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"descending colon\") OR (\"descending down\"))) or (\"descending motor\"))".
• Removing quotes may allow a broader search: (((( descending colon ) OR ( descending down ))) or ( descending motor )).
• Adding a wildcard symbol may retrieve word variants: (((("descending colon") OR ("descending down"))) or ("descending motor"))*.