Perhaps you should try some spelling variations:
complex control » complex controls (Expand Search), complement control (Expand Search)
campos johan » camps johan (Expand Search), campos john (Expand Search), campos joao (Expand Search)
most complex » most complete (Expand Search), cst complex (Expand Search), foot complex (Expand Search)
nano carlos » cano carlos (Expand Search), nino carlos (Expand Search), nuno carlos (Expand Search)
carlos nar » carlos nara (Expand Search), carlos nejar (Expand Search), carlos nardi (Expand Search)
control n » control nf (Expand Search), control non (Expand Search), control new (Expand Search)
nacl nano » nacl kno (Expand Search), nacl nabr (Expand Search), nacl naoh (Expand Search)
l campos » e campos (Expand Search), gil campos (Expand Search), en campos (Expand Search)
7.5 nacl » 3.5 nacl (Expand Search), 0.9 nacl (Expand Search)
johan n » johan a (Expand Search), johan _ (Expand Search), johan c (Expand Search)
5 most » 25 most (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 l campos johan n ) OR ((( 5 most complex control n ) OR ( 7.5 nacl nano carlos nar ))))~.
• Adding a wildcard symbol may retrieve word variants: (( j l campos johan n ) or ((( 5 most complex control n ) or ( 7.5 nacl nano carlos nar ))))*.