Talvez deva tentar algumas variações de ortografia:
computer based » computer aided (Expandir a Pesquisa)
compares bases » compared cases (Expandir a Pesquisa), comparison bases (Expandir a Pesquisa), companies based (Expandir a Pesquisa)
nat computers » what computers (Expandir a Pesquisa), iet computers (Expandir a Pesquisa), can computers (Expandir a Pesquisa)
computers can » computers a (Expandir a Pesquisa), computers _ (Expandir a Pesquisa)
unit compares » unit compared (Expandir a Pesquisa), units compared (Expandir a Pesquisa), unit comparison (Expandir a Pesquisa)
yl computer » il computer (Expandir a Pesquisa), dal computer (Expandir a Pesquisa), apl computer (Expandir a Pesquisa)
bases now » cases now (Expandir a Pesquisa), bases n (Expandir a Pesquisa), bases com (Expandir a Pesquisa)
can non » dan non (Expandir a Pesquisa), than non (Expandir a Pesquisa)
3 unit » _ unit (Expandir a Pesquisa), a unit (Expandir a Pesquisa)
1 yl » 2 yl (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: (((( _ nat computers can non ) or ( 1 yl computer based non ))) or ( 3 unit compares bases now ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( _ nat computers can non ) OR ( 1 yl computer based non ))) OR ( 3 unit compares bases now )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( _ nat computers can non ) or ( 1 yl computer based non ))) or ( 3 unit compares bases now ))*.