Perhaps you should try some spelling variations:
complejos como » complejo como (Expand Search), complejas como (Expand Search), complejos homo (Expand Search)
en complejos » un complejo (Expand Search), de complejos (Expand Search), y complejos (Expand Search)
carlos nejad » carlos nejar (Expand Search), carlos tejada (Expand Search), carlos vejar (Expand Search)
combe colin » combs colin (Expand Search), cooke colin (Expand Search), combe caroline (Expand Search)
kcl carlos » kuhl carlos (Expand Search), akel carlos (Expand Search), gil carlos (Expand Search)
7.5 nacl » 3.5 nacl (Expand Search), 0.9 nacl (Expand Search)
e combe » e combes (Expand Search), e coombe (Expand Search), e combs (Expand Search)
colin n » colin a (Expand Search), colin d (Expand Search), colin _ (Expand Search)
5 en » 5 n (Expand Search), 5 e (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 e combe colin n ) or ((( 5 en complejos como o ) or ( 7.5 nacl kcl carlos nejad ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( j e combe colin n ) OR ((( 5 en complejos como o ) OR ( 7.5 nacl kcl carlos nejad )))).
• Adding a wildcard symbol may retrieve word variants: (( j e combe colin n ) or ((( 5 en complejos como o ) or ( 7.5 nacl kcl carlos nejad ))))*.