Talvez deva tentar algumas variações de ortografia:
thoracic cardiovasc » thorac cardiovasc (Expandir a Pesquisa), thoracic cardiac (Expandir a Pesquisa), thoracic cardiovascular (Expandir a Pesquisa)
cardiovasc surg » cardiovasc surgery (Expandir a Pesquisa), cardiovasc sci (Expandir a Pesquisa)
semin thoracic » vein thoracic (Expandir a Pesquisa), benign thoracic (Expandir a Pesquisa), lamina thoracic (Expandir a Pesquisa)
surg pediatric » surgery pediatric (Expandir a Pesquisa), during pediatric (Expandir a Pesquisa), survey pediatric (Expandir a Pesquisa)
care surge » care sorge (Expandir a Pesquisa), care surgery (Expandir a Pesquisa), care surgeon (Expandir a Pesquisa)
care surg » care sural (Expandir a Pesquisa), care sub (Expandir a Pesquisa), care suez (Expandir a Pesquisa)
care sars » care says (Expandir a Pesquisa), care saqs (Expandir a Pesquisa), care sparc (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: semin thoracic cardiovasc surg pediatric ((((care surg) OR (care surge))) or (care sars)) annu~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: semin thoracic cardiovasc surg pediatric ((((care surg) OR (care surge))) OR (care sars)) annu.
• "As palabras AND, OR e NOT podem gerar pesquisas incorrectas; tente utilizar aspas": "semin thoracic cardiovasc surg pediatric ((((care surg) OR (care surge))) or (care sars)) annu".
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: semin thoracic cardiovasc surg pediatric ((((care surg) OR (care surge))) or (care sars)) annu*.