Talvez deva tentar algumas variações de ortografia:
cardiovascular reasons » cardiovascular reactions (Expandir a Pesquisa), cardiovascular reasoning (Expandir a Pesquisa), cardiovascular response (Expandir a Pesquisa)
aortic cardiovascular » thoracic cardiovascular (Expandir a Pesquisa), diabetic cardiovascular (Expandir a Pesquisa), chronic cardiovascular (Expandir a Pesquisa)
reasons pediatric » swenson's pediatric (Expandir a Pesquisa), versus pediatric (Expandir a Pesquisa), reviews pediatric (Expandir a Pesquisa)
german aortic » german ortiz (Expandir a Pesquisa), human aortic (Expandir a Pesquisa)
pediatric rpe » pediatric re (Expandir a Pesquisa), pediatric rare (Expandir a Pesquisa), pediatric rat (Expandir a Pesquisa)
rpe leads » age leads (Expandir a Pesquisa), cre leads (Expandir a Pesquisa), e leads (Expandir a Pesquisa)
annu » ann (Expandir a Pesquisa), anna (Expandir a Pesquisa), anne (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: german aortic cardiovascular reasons pediatric rpe leads annu~.
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: german aortic cardiovascular reasons pediatric rpe leads annu*.