Talvez deva tentar algumas variações de ortografia:
research systems » research synthesis (Expandir a Pesquisa)
mental research » dental research (Expandir a Pesquisa), central research (Expandir a Pesquisa), neonatal research (Expandir a Pesquisa)
prevent nerve » prevent neural (Expandir a Pesquisa), prevent new (Expandir a Pesquisa), seventh nerve (Expandir a Pesquisa)
systems dss » systems cdss (Expandir a Pesquisa), system dss (Expandir a Pesquisa), systems does (Expandir a Pesquisa)
cena nerve » renal nerve (Expandir a Pesquisa), beta nerve (Expandir a Pesquisa), central nerve (Expandir a Pesquisa)
nerve cat » nerve can (Expandir a Pesquisa), nerve ct (Expandir a Pesquisa), nerve cut (Expandir a Pesquisa)
i prevent » i prevents (Expandir a Pesquisa), ii prevent (Expandir a Pesquisa), _ prevent (Expandir a Pesquisa)
j mental » j mengual (Expandir a Pesquisa), j mena (Expandir a Pesquisa), j mehta (Expandir a Pesquisa)
cat dis » cat did (Expandir a Pesquisa), cat diets (Expandir a Pesquisa), cat bias (Expandir a Pesquisa)
nerve c » nerve cn (Expandir a Pesquisa), nerve co (Expandir a Pesquisa), nerve ct (Expandir a Pesquisa)
a cena » na cena (Expandir a Pesquisa)
c dis » c dias (Expandir a Pesquisa), c disc (Expandir a Pesquisa), c dos (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: (((( a cena nerve cat dis ) or ( i prevent nerve c dis ))) or ( j mental research systems dss ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( a cena nerve cat dis ) OR ( i prevent nerve c dis ))) OR ( j mental research systems dss )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( a cena nerve cat dis ) or ( i prevent nerve c dis ))) or ( j mental research systems dss ))*.