Perhaps you should try some spelling variations:
metil complex » metal complex (Expand Search), metals complex (Expand Search), met complex (Expand Search)
semino carlos » serrano carlos (Expand Search), bacino carlos (Expand Search), solano carlos (Expand Search)
complex text » complete text (Expand Search), complex tear (Expand Search), complex team (Expand Search)
carlos novoa » carlos novo (Expand Search), carlos nova (Expand Search), carlos nava (Expand Search)
comps con » compost con (Expand Search), comps los (Expand Search)
text ngoa » text nlo (Expand Search), text non (Expand Search), text now (Expand Search)
7.5 nacl » 3.5 nacl (Expand Search), 0.9 nacl (Expand Search)
con net » con nee (Expand Search), non net (Expand Search), upon net (Expand Search)
5 metil » 5 methyl (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.

• The words AND, OR and NOT may confuse the search; try adding quotes: "(( j m comps con net ) OR ((( 5 metil complex text ngoa ) OR ( 7.5 nacl semino carlos novoa ))))~".
• Adding a wildcard symbol may retrieve word variants: (( j m comps con net ) OR ((( 5 metil complex text ngoa ) OR ( 7.5 nacl semino carlos novoa ))))*.