Talvez deva tentar algumas variações de ortografia:
computer course » computer courses (Expandir a Pesquisa), computer discourse (Expandir a Pesquisa), computing course (Expandir a Pesquisa)
daily computer » daily compared (Expandir a Pesquisa), ray computer (Expandir a Pesquisa)
natl compared » nacl compared (Expandir a Pesquisa), nail compared (Expandir a Pesquisa), acl compared (Expandir a Pesquisa)
compared de » comparee de (Expandir a Pesquisa), compare de (Expandir a Pesquisa), compared do (Expandir a Pesquisa)
course non » course can (Expandir a Pesquisa), course na (Expandir a Pesquisa), course new (Expandir a Pesquisa)
dna clamp » a clamp (Expandir a Pesquisa)
de near » ice near (Expandir a Pesquisa)
a daily » _ daily (Expandir a Pesquisa)
j dna » _ dna (Expandir a Pesquisa), a dna (Expandir a Pesquisa), 1 dna (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": "(((( _ natl compared de near ) OR ( j dna clamp _ newts ))) OR ( a daily computer course non ))~".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( _ natl compared de near ) OR ( j dna clamp _ newts ))) OR ( a daily computer course non ))*.