Talvez deva tentar algumas variações de ortografia:
research system » research systems (Expandir a Pesquisa)
lung research » aging research (Expandir a Pesquisa)
center nerve » cancer nerve (Expandir a Pesquisa), center nurse (Expandir a Pesquisa), letter nerve (Expandir a Pesquisa)
really nerve » early nerve (Expandir a Pesquisa), really never (Expandir a Pesquisa), really needed (Expandir a Pesquisa)
nerve rat » nerve rate (Expandir a Pesquisa), nerve root (Expandir a Pesquisa), nerve a (Expandir a Pesquisa)
system de » system der (Expandir a Pesquisa), system delay (Expandir a Pesquisa)
j center » j centner (Expandir a Pesquisa), j centeno (Expandir a Pesquisa), j cestero (Expandir a Pesquisa)
rat disc » rat dose (Expandir a Pesquisa)
i really » a really (Expandir a Pesquisa)
1 lung » a lung (Expandir a Pesquisa)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

Pode obter mais resultados ajustando a pesquisa.

• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( j center nerve rat disc ) OR ( i really nerve _ dias ))) OR ( 1 lung research system de ))~.
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( j center nerve rat disc ) or ( i really nerve _ dias ))) or ( 1 lung research system de ))*.