Talvez deva tentar algumas variações de ortografia:
compra das » compras das (Expandir a Pesquisa), compra dos (Expandir a Pesquisa), compra da (Expandir a Pesquisa)
nat compra » na compra (Expandir a Pesquisa), la compra (Expandir a Pesquisa), da compra (Expandir a Pesquisa)
compr can » comp can (Expandir a Pesquisa), computer can (Expandir a Pesquisa), compared can (Expandir a Pesquisa)
natl camp » al camp (Expandir a Pesquisa)
camp can » clamp can (Expandir a Pesquisa), camp ca (Expandir a Pesquisa), amp can (Expandir a Pesquisa)
can netw » can new (Expandir a Pesquisa), can newts (Expandir a Pesquisa), can now (Expandir a Pesquisa)
can net » can new (Expandir a Pesquisa), dan net (Expandir a Pesquisa), can nt (Expandir a Pesquisa)
das non » das n.n (Expandir a Pesquisa), das noz (Expandir a Pesquisa), das nina (Expandir a Pesquisa)
j natl » j nail (Expandir a Pesquisa), _ natl (Expandir a Pesquisa), j natali (Expandir a Pesquisa)
j nat » j nart (Expandir a Pesquisa), _ nat (Expandir a Pesquisa), a nat (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 natl compr can net ) OR ( j natl camp can netw ))) OR ( j nat compra das non ))~.
• "As palabras AND, OR e NOT podem gerar pesquisas incorrectas; tente utilizar aspas": "(((( j natl compr can net ) OR ( j natl camp can netw ))) OR ( j nat compra das non ))*".