Talvez deva tentar algumas variações de ortografia:
optimal methods » optical methods (Expandir a Pesquisa), optimal method (Expandir a Pesquisa), optical method (Expandir a Pesquisa)
oral methods » oral method (Expandir a Pesquisa), viral methods (Expandir a Pesquisa), dual methods (Expandir a Pesquisa)
methods role » methods real (Expandir a Pesquisa), methods risk (Expandir a Pesquisa)
anal method » manual method (Expandir a Pesquisa), analog method (Expandir a Pesquisa), animal method (Expandir a Pesquisa)
methods cam » methods can (Expandir a Pesquisa), method cam (Expandir a Pesquisa), methods cad (Expandir a Pesquisa)
j optimal » _ optimal (Expandir a Pesquisa), d optimal (Expandir a Pesquisa), a optimal (Expandir a Pesquisa)
method a » method _ (Expandir a Pesquisa)
j anal » j anil (Expandir a Pesquisa), j anibal (Expandir a Pesquisa)
j oral » 4 oral (Expandir a Pesquisa), 1 oral (Expandir a Pesquisa), 3 oral (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 anal method a ) or ( j oral methods role ))) or ( j optimal methods cam ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( j anal method a ) OR ( j oral methods role ))) OR ( j optimal methods cam )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( j anal method a ) or ( j oral methods role ))) or ( j optimal methods cam ))*.