Perhaps you should try some spelling variations:
maier viola » lanier viola (Expand Search), beier viola (Expand Search), walter viola (Expand Search)
mater chen » mayer chen (Expand Search), matter chern (Expand Search), walter chen (Expand Search)
maier biol » maier i.l (Expand Search), maier il (Expand Search)
biol med » biol res (Expand Search), mol med (Expand Search)
j mateos » m mateos (Expand Search), j mateo (Expand Search), a mateos (Expand Search)
j mater » j matear (Expand Search), j mather (Expand Search), j mateu (Expand Search)
j mates » j mateus (Expand Search), j mathes (Expand Search), j mateu (Expand Search)
ochem a » jochem a (Expand Search)
a maier » _ maier (Expand Search), a mailed (Expand Search)
viola d » viola de (Expand Search), viola _ (Expand Search), viola a (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.

• If you are trying to use Boolean operators, they must be ALL CAPS: (( j mater chen b maier biol med ) OR ( ((j mates) OR (j mateos)) ochem a maier viola d ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( j mater chen b maier biol med ) or ( ((j mates) OR (j mateos)) ochem a maier viola d ))~".
• Adding a wildcard symbol may retrieve word variants: (( j mater chen b maier biol med ) or ( ((j mates) OR (j mateos)) ochem a maier viola d ))*.