Talvez deva tentar algumas variações de ortografia:
threat levels » threat level (Expandir a Pesquisa), three levels (Expandir a Pesquisa), three level (Expandir a Pesquisa)
mental nerve » ventral nerve (Expandir a Pesquisa), central nerve (Expandir a Pesquisa), renal nerve (Expandir a Pesquisa)
nerve causes » nerve caused (Expandir a Pesquisa), nerve cases (Expandir a Pesquisa), nerve cause (Expandir a Pesquisa)
causes does » causes des (Expandir a Pesquisa), cause does (Expandir a Pesquisa), campuses does (Expandir a Pesquisa)
levels cat » levels can (Expandir a Pesquisa), levels case (Expandir a Pesquisa), levels caix (Expandir a Pesquisa)
bent nerve » absent nerve (Expandir a Pesquisa), dental nerve (Expandir a Pesquisa), benign nerve (Expandir a Pesquisa)
j threat » al threat (Expandir a Pesquisa)
j mental » j mengual (Expandir a Pesquisa), j mena (Expandir a Pesquisa), j mehta (Expandir a Pesquisa)
cat dis » cat did (Expandir a Pesquisa), cat diets (Expandir a Pesquisa), cat diet (Expandir a Pesquisa)
nerve a » nerve _ (Expandir a Pesquisa)
l bent » l benth (Expandir a Pesquisa), l bengt (Expandir a Pesquisa), l bento (Expandir a Pesquisa)
a dos » e dos (Expandir a Pesquisa), a dog (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: (( j threat levels cat dis ) or ((( j mental nerve causes does ) or ( l bent nerve a dos ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( j threat levels cat dis ) OR ((( j mental nerve causes does ) OR ( l bent nerve a dos )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( j threat levels cat dis ) or ((( j mental nerve causes does ) or ( l bent nerve a dos ))))*.