Talvez deva tentar algumas variações de ortografia:
held computers » held computer (Expandir a Pesquisa), handheld computers (Expandir a Pesquisa)
computers can » computers a (Expandir a Pesquisa), computers _ (Expandir a Pesquisa)
natal compare » data compare (Expandir a Pesquisa), fetal compared (Expandir a Pesquisa), metal compared (Expandir a Pesquisa)
compare a » compare _ (Expandir a Pesquisa)
camp can » clamp can (Expandir a Pesquisa), camp ca (Expandir a Pesquisa), amp can (Expandir a Pesquisa)
ac camp » c camp (Expandir a Pesquisa), amp camp (Expandir a Pesquisa)
can now » can non (Expandir a Pesquisa), can new (Expandir a Pesquisa), can ngoc (Expandir a Pesquisa)
_ natal » _ natural (Expandir a Pesquisa)
j held » j head (Expandir a Pesquisa)
a now » a new (Expandir a Pesquisa), a non (Expandir a Pesquisa), _ now (Expandir a Pesquisa)
j ac » j a (Expandir a Pesquisa), j c (Expandir a Pesquisa), j al (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 ac camp can (netw OR new) ) or ((( j held computers can now ) or ( _ natal compare a now ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( j ac camp can (netw OR new) ) OR ((( j held computers can now ) OR ( _ natal compare a now )))).
• "As palabras AND, OR e NOT podem gerar pesquisas incorrectas; tente utilizar aspas": "(( j ac camp can (netw OR new) ) or ((( j held computers can now ) or ( _ natal compare a now ))))".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( j ac camp can (netw OR new) ) or ((( j held computers can now ) or ( _ natal compare a now ))))*.