Talvez deva tentar algumas variações de ortografia:
disease levels » disease level (Expandir a Pesquisa), dismutase levels (Expandir a Pesquisa), decrease levels (Expandir a Pesquisa)
developed teen » developed test (Expandir a Pesquisa), developed open (Expandir a Pesquisa), developed between (Expandir a Pesquisa)
fds developed » foods developed (Expandir a Pesquisa), has developed (Expandir a Pesquisa), films developed (Expandir a Pesquisa)
levels rather » level rather (Expandir a Pesquisa), cells rather (Expandir a Pesquisa)
drug disease » lung disease (Expandir a Pesquisa), drug release (Expandir a Pesquisa)
dose levels » noise levels (Expandir a Pesquisa)
drugs fds » drugs fda (Expandir a Pesquisa), drugs ads (Expandir a Pesquisa), drugs frids (Expandir a Pesquisa)
drug dose » drug dosage (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: (( drugs fds developed teen ) or ((( drug dose levels rather ) or ( drug disease levels over ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( drugs fds developed teen ) OR ((( drug dose levels rather ) OR ( drug disease levels over )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( drugs fds developed teen ) or ((( drug dose levels rather ) or ( drug disease levels over ))))*.