Perhaps you should try some spelling variations:
best observed » best served (Expand Search), event observed (Expand Search)
observed cat » observed data (Expand Search), observed case (Expand Search), observed care (Expand Search)
crest nerve » treat nerve (Expand Search), crest derived (Expand Search), current nerve (Expand Search)
nerve cyst » nerve cystic (Expand Search), nerve case (Expand Search), nerve ct (Expand Search)
beat nerve » bent nerve (Expand Search), treat nerve (Expand Search), heart nerve (Expand Search)
nerve cat » nerve can (Expand Search), nerve ct (Expand Search), nerve cut (Expand Search)
j crest » _ crest (Expand Search), a crest (Expand Search), 5 crest (Expand Search)
cat dis » cat diets (Expand Search), cat bias (Expand Search), cat diet (Expand Search)
cat did » coast did (Expand Search), what did (Expand Search), past did (Expand Search)
j beat » j beaty (Expand Search), j bean (Expand Search), j bear (Expand Search)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( j crest nerve cyst due ) or ((( j beat nerve cat dis ) or ( j best observed cat did ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( j crest nerve cyst due ) OR ((( j beat nerve cat dis ) OR ( j best observed cat did )))).
• Adding a wildcard symbol may retrieve word variants: (( j crest nerve cyst due ) or ((( j beat nerve cat dis ) or ( j best observed cat did ))))*.