Talvez deva tentar algumas variações de ortografia:
central nerve » ventral nerve (Expandir a Pesquisa), central nervous (Expandir a Pesquisa), central neural (Expandir a Pesquisa)
nerve system » nervous system (Expandir a Pesquisa), drive system (Expandir a Pesquisa)
absent merve » absent nerve (Expandir a Pesquisa), absent gene (Expandir a Pesquisa), absent men (Expandir a Pesquisa)
system dis » system dias (Expandir a Pesquisa), system dcs (Expandir a Pesquisa), system di (Expandir a Pesquisa)
cent merve » cin merve (Expandir a Pesquisa), cengiz merve (Expandir a Pesquisa), celenk merve (Expandir a Pesquisa)
j central » 1hfj central (Expandir a Pesquisa)
merve can » nerve can (Expandir a Pesquisa)
can diets » cane diets (Expandir a Pesquisa), can diet (Expandir a Pesquisa), corn diets (Expandir a Pesquisa)
j absent » _ absent (Expandir a Pesquisa), l absent (Expandir a Pesquisa), 17 absent (Expandir a Pesquisa)
i cent » i cento (Expandir a Pesquisa), ai cent (Expandir a Pesquisa), ii cent (Expandir a Pesquisa)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

Pode obter mais resultados ajustando a pesquisa.

• "As palabras AND, OR e NOT podem gerar pesquisas incorrectas; tente utilizar aspas": "(((( j central nerve system dis ) OR ( i cent merve can diets ))) OR ( j absent merve can diets ))~".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( j central nerve system dis ) OR ( i cent merve can diets ))) OR ( j absent merve can diets ))*.