Talvez deva tentar algumas variações de ortografia:
cobalt complexes » covalent complexes (Expandir a Pesquisa)
complexes than » complexes thin (Expandir a Pesquisa), complexes thion (Expandir a Pesquisa), complexes change (Expandir a Pesquisa)
cooper jason » cooper john (Expandir a Pesquisa), cooper alan (Expandir a Pesquisa), cooper james (Expandir a Pesquisa)
carlos roger » carlos rogerio (Expandir a Pesquisa), carlos romero (Expandir a Pesquisa), carlos robert (Expandir a Pesquisa)
kno carlos » knopf carlos (Expandir a Pesquisa), cano carlos (Expandir a Pesquisa), nino carlos (Expandir a Pesquisa)
than ngoc » thanh ngoc (Expandir a Pesquisa), thuan ngoc (Expandir a Pesquisa), tran ngoc (Expandir a Pesquisa)
a cooper » _ cooper (Expandir a Pesquisa), m cooper (Expandir a Pesquisa)
5 cobalt » _ cobalt (Expandir a Pesquisa), n cobalt (Expandir a Pesquisa), a cobalt (Expandir a Pesquisa)
7.5 nacl » 3.5 nacl (Expandir a Pesquisa), 0.9 nacl (Expandir a Pesquisa)
nacl kno » nacl nano (Expandir a Pesquisa), nacl en (Expandir a Pesquisa), nacl kcl (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 a cooper jason _ ) or ((( 5 cobalt complexes than ngoc ) or ( 7.5 nacl kno carlos roger ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( j a cooper jason _ ) OR ((( 5 cobalt complexes than ngoc ) OR ( 7.5 nacl kno carlos roger )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( j a cooper jason _ ) or ((( 5 cobalt complexes than ngoc ) or ( 7.5 nacl kno carlos roger ))))*.