Talvez deva tentar algumas variações de ortografia:
diet develop » diet developed (Expandir a Pesquisa), diets developed (Expandir a Pesquisa), diet developing (Expandir a Pesquisa)
develop them » develop type (Expandir a Pesquisa), develop age (Expandir a Pesquisa)
drugs does » drugs do (Expandir a Pesquisa)
does liver » does life (Expandir a Pesquisa), does laser (Expandir a Pesquisa), drives liver (Expandir a Pesquisa)
liver over » liver liver (Expandir a Pesquisa), layer over (Expandir a Pesquisa), cover over (Expandir a Pesquisa)
dose level » dose levels (Expandir a Pesquisa), noise level (Expandir a Pesquisa), dose live (Expandir a Pesquisa)
level ther » level theory (Expandir a Pesquisa), level rather (Expandir a Pesquisa), levels other (Expandir a Pesquisa)
drug diet » drugs diet (Expandir a Pesquisa), drug de (Expandir a Pesquisa), drug does (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.

• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( drug diet develop them ) OR ((( drugs does liver over ) OR ( drug dose level ther ))))~.
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( drug diet develop them ) or ((( drugs does liver over ) or ( drug dose level ther ))))*.