Talvez deva tentar algumas variações de ortografia:
current cancer » recurrent cancer (Expandir a Pesquisa), current concerns (Expandir a Pesquisa), current concept (Expandir a Pesquisa)
cancer system » cancer systems (Expandir a Pesquisa), cancer systemic (Expandir a Pesquisa), cancer stem (Expandir a Pesquisa)
mental nerve » ventral nerve (Expandir a Pesquisa), central nerve (Expandir a Pesquisa), renal nerve (Expandir a Pesquisa)
system sdcs » system dcs (Expandir a Pesquisa), system sedds (Expandir a Pesquisa), system bddcs (Expandir a Pesquisa)
bent nerve » absent nerve (Expandir a Pesquisa), dental nerve (Expandir a Pesquisa), benign nerve (Expandir a Pesquisa)
nerve salt » nerve split (Expandir a Pesquisa), nerve safe (Expandir a Pesquisa), nerve self (Expandir a Pesquisa)
j mental » j mengual (Expandir a Pesquisa), j mena (Expandir a Pesquisa), j mehta (Expandir a Pesquisa)
case di » case dti (Expandir a Pesquisa), case d (Expandir a Pesquisa), case de (Expandir a Pesquisa)
i bent » i benth (Expandir a Pesquisa), i benet (Expandir a Pesquisa), i bento (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 bent nerve salt diet ) OR ( i current cancer system sdcs ))) OR ( j mental nerve case di ))~".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( i bent nerve salt diet ) OR ( i current cancer system sdcs ))) OR ( j mental nerve case di ))*.