Talvez deva tentar algumas variações de ortografia:
ventral nerve » femoral nerve (Expandir a Pesquisa)
benign peptic » benign hepatic (Expandir a Pesquisa), benign cystic (Expandir a Pesquisa)
nerve system » nervous system (Expandir a Pesquisa), drive system (Expandir a Pesquisa)
cento nerve » bent nerve (Expandir a Pesquisa), central nerve (Expandir a Pesquisa), mental nerve (Expandir a Pesquisa)
system dis » system dias (Expandir a Pesquisa), system dcs (Expandir a Pesquisa), system di (Expandir a Pesquisa)
peptic cns » peptide cns (Expandir a Pesquisa), peptic cells (Expandir a Pesquisa)
i ventral » _ ventral (Expandir a Pesquisa), a ventral (Expandir a Pesquisa), 2 ventral (Expandir a Pesquisa)
nerve cn » nerve can (Expandir a Pesquisa), nerve c (Expandir a Pesquisa), nerve cat (Expandir a Pesquisa)
j benign » j benigno (Expandir a Pesquisa), _ benign (Expandir a Pesquisa), a benign (Expandir a Pesquisa)
i cento » a cento (Expandir a Pesquisa), i censo (Expandir a Pesquisa), i centeno (Expandir a Pesquisa)
cns dis » cns axis (Expandir a Pesquisa)
cn dcs » can dcs (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": "(((( i cento nerve system dis ) OR ( i ventral nerve cn dcs ))) OR ( j benign peptic cns dis ))~".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( i cento nerve system dis ) OR ( i ventral nerve cn dcs ))) OR ( j benign peptic cns dis ))*.