Talvez deva tentar algumas variações de ortografia:
active systems » active systemic (Expandir a Pesquisa), adaptive systems (Expandir a Pesquisa), drive systems (Expandir a Pesquisa)
prevent nerve » prevent neural (Expandir a Pesquisa), prevent new (Expandir a Pesquisa), seventh nerve (Expandir a Pesquisa)
central nerve » ventral nerve (Expandir a Pesquisa), central nervous (Expandir a Pesquisa), central neural (Expandir a Pesquisa)
absent active » absence active (Expandir a Pesquisa), absent native (Expandir a Pesquisa)
systems dds » systems dss (Expandir a Pesquisa), systems sedds (Expandir a Pesquisa), systems does (Expandir a Pesquisa)
j central » 1hfj central (Expandir a Pesquisa)
_ absent » _ absence (Expandir a Pesquisa)
nerve a » nerve _ (Expandir a Pesquisa)
a due » _ due (Expandir a Pesquisa), 2 due (Expandir a Pesquisa), i due (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: (( _ prevent nerve a due ) or ((( j central nerve a due ) or ( _ absent active systems dds ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( _ prevent nerve a due ) OR ((( j central nerve a due ) OR ( _ absent active systems dds )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( _ prevent nerve a due ) or ((( j central nerve a due ) or ( _ absent active systems dds ))))*.