Talvez deva tentar algumas variações de ortografia:
research synthesis » starch synthesis (Expandir a Pesquisa)
mental research » dental research (Expandir a Pesquisa), central research (Expandir a Pesquisa), neonatal research (Expandir a Pesquisa)
century nerve » century reserve (Expandir a Pesquisa), century survey (Expandir a Pesquisa), century energy (Expandir a Pesquisa)
synthesis do » synthesis dos (Expandir a Pesquisa), synthesis de (Expandir a Pesquisa), synthesis does (Expandir a Pesquisa)
cent nerve » bent nerve (Expandir a Pesquisa), recent nerve (Expandir a Pesquisa), crest nerve (Expandir a Pesquisa)
nerve cat » nerve can (Expandir a Pesquisa), nerve case (Expandir a Pesquisa), nerve a (Expandir a Pesquisa)
j mental » j mengual (Expandir a Pesquisa), j mehta (Expandir a Pesquisa), j mena (Expandir a Pesquisa)
cat dcs » can dcs (Expandir a Pesquisa)
i cent » i cento (Expandir a Pesquisa), ai cent (Expandir a Pesquisa), ii cent (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: (((( a century nerve cat dcs ) or ( i cent nerve _ dis ))) or ( j mental research synthesis do ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( a century nerve cat dcs ) OR ( i cent nerve _ dis ))) OR ( j mental research synthesis do )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( a century nerve cat dcs ) or ( i cent nerve _ dis ))) or ( j mental research synthesis do ))*.