Talvez deva tentar algumas variações de ortografia:
computer course » computer courses (Expandir a Pesquisa), computer discourse (Expandir a Pesquisa), computing course (Expandir a Pesquisa)
natl compared » nacl compared (Expandir a Pesquisa), nail compared (Expandir a Pesquisa), acl compared (Expandir a Pesquisa)
compared cdse » compared case (Expandir a Pesquisa), compared cases (Expandir a Pesquisa), compared de (Expandir a Pesquisa)
ray computer » ray computed (Expandir a Pesquisa), uy computer (Expandir a Pesquisa)
course non » course can (Expandir a Pesquisa), course na (Expandir a Pesquisa), course new (Expandir a Pesquisa)
cdse near » case near (Expandir a Pesquisa), cds near (Expandir a Pesquisa), use near (Expandir a Pesquisa)
dna clamp » a clamp (Expandir a Pesquisa)
j dna » _ dna (Expandir a Pesquisa), a dna (Expandir a Pesquisa), 1 dna (Expandir a Pesquisa)
a ray » x ray (Expandir a Pesquisa), a rat (Expandir a Pesquisa), _ ray (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: (((( _ natl compared cdse near ) OR ( j dna clamp _ newts ))) OR ( a ray computer course non ))~.
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( _ natl compared cdse near ) or ( j dna clamp _ newts ))) or ( a ray computer course non ))*.