Talvez deva tentar algumas variações de ortografia:
complex concept » complex concepts (Expandir a Pesquisa), complex context (Expandir a Pesquisa), complex connects (Expandir a Pesquisa)
combat colon » combat covid (Expandir a Pesquisa), combat boot (Expandir a Pesquisa)
arnt complex » art complex (Expandir a Pesquisa), learnt complex (Expandir a Pesquisa), agent complex (Expandir a Pesquisa)
knopf carlos » prof carlos (Expandir a Pesquisa)
carlos lara » carlos lima (Expandir a Pesquisa), carlos lacerda (Expandir a Pesquisa), carlos lazaro (Expandir a Pesquisa)
nacl knopf » nacl kno (Expandir a Pesquisa)
colon new » colony new (Expandir a Pesquisa), color new (Expandir a Pesquisa), colon need (Expandir a Pesquisa)
concept a » concept _ (Expandir a Pesquisa)
7.5 nacl » 3.5 nacl (Expandir a Pesquisa), 0.9 nacl (Expandir a Pesquisa)
e arnt » e arnot (Expandir a Pesquisa), e arntz (Expandir a Pesquisa), _ arnt (Expandir a Pesquisa)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

Pode obter mais resultados ajustando a pesquisa.

• Performing a fuzzy search may retrieve terms with similar spellings: (( j _ combat colon new ) or ((( e arnt complex concept a ) or ( 7.5 nacl knopf carlos lara ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( j _ combat colon new ) OR ((( e arnt complex concept a ) OR ( 7.5 nacl knopf carlos lara )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( j _ combat colon new ) or ((( e arnt complex concept a ) or ( 7.5 nacl knopf carlos lara ))))*.