Talvez deva tentar algumas variações de ortografia:
insights learned » insights gleaned (Expandir a Pesquisa), insights gained (Expandir a Pesquisa), insights lead (Expandir a Pesquisa)
hearts insights » health insights (Expandir a Pesquisa), plants insights (Expandir a Pesquisa), traits insights (Expandir a Pesquisa)
heart insights » health insights (Expandir a Pesquisa), early insights (Expandir a Pesquisa)
insights hard » insights hand (Expandir a Pesquisa), insights have (Expandir a Pesquisa), insights ear (Expandir a Pesquisa)
clin hearts » skin hearts (Expandir a Pesquisa), twin hearts (Expandir a Pesquisa), canine hearts (Expandir a Pesquisa)
core throat » sore throat (Expandir a Pesquisa), pore throat (Expandir a Pesquisa), sore throats (Expandir a Pesquisa)
learned non » learned how (Expandir a Pesquisa), learned along (Expandir a Pesquisa), learned from (Expandir a Pesquisa)
pain heart » brain heart (Expandir a Pesquisa), pain health (Expandir a Pesquisa), pain part (Expandir a Pesquisa)
hard core » hard coal (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: (( clin hearts insights hard core throat ) OR ( pain heart insights learned non thrust ))~.
• "As palabras AND, OR e NOT podem gerar pesquisas incorrectas; tente utilizar aspas": "(( clin hearts insights hard core throat ) OR ( pain heart insights learned non thrust ))".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( clin hearts insights hard core throat ) OR ( pain heart insights learned non thrust ))*.