Talvez deva tentar algumas variações de ortografia:
metal complex » metal complexes (Expandir a Pesquisa)
cooper jason » cooper john (Expandir a Pesquisa), cooper alan (Expandir a Pesquisa), cooper james (Expandir a Pesquisa)
caso4 carlos » caso carlos (Expandir a Pesquisa), caro carlos (Expandir a Pesquisa), casal carlos (Expandir a Pesquisa)
complex trs » complex tris (Expandir a Pesquisa), complex tears (Expandir a Pesquisa), complex trans (Expandir a Pesquisa)
carlos yoel » carlos joel (Expandir a Pesquisa), carlos noel (Expandir a Pesquisa), carlos hoelz (Expandir a Pesquisa)
nacl caso4 » nacl na2so4 (Expandir a Pesquisa)
l cooper » i cooper (Expandir a Pesquisa), j cooper (Expandir a Pesquisa), m cooper (Expandir a Pesquisa)
trs ngoc » tra ngoc (Expandir a Pesquisa), tran ngoc (Expandir a Pesquisa), tram ngoc (Expandir a Pesquisa)
jason a » jason _ (Expandir a Pesquisa)
5 metal » 5 methyl (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 l cooper jason a ) or ((( 5 metal complex trs ngoc ) or ( 3.5 nacl caso4 carlos yoel ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( j l cooper jason a ) OR ((( 5 metal complex trs ngoc ) OR ( 3.5 nacl caso4 carlos yoel )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( j l cooper jason a ) or ((( 5 metal complex trs ngoc ) or ( 3.5 nacl caso4 carlos yoel ))))*.