Talvez deva tentar algumas variações de ortografia:
crest derived » host derived (Expandir a Pesquisa)
derived ther » derived rather (Expandir a Pesquisa), derived three (Expandir a Pesquisa), derived th1 (Expandir a Pesquisa)
doses level » dose level (Expandir a Pesquisa), does level (Expandir a Pesquisa), bones level (Expandir a Pesquisa)
dose levels » noise levels (Expandir a Pesquisa)
levels ther » levels other (Expandir a Pesquisa), levels rather (Expandir a Pesquisa), levels three (Expandir a Pesquisa)
drug crest » drug cross (Expandir a Pesquisa), drug crystal (Expandir a Pesquisa)
drug doses » drug disease (Expandir a Pesquisa)
level ther » level theory (Expandir a Pesquisa), level rather (Expandir a Pesquisa), levels other (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: (( drug crest derived ther ) or ((( drug doses level ther ) or ( drug dose levels ther ))))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (( drug crest derived ther ) OR ((( drug doses level ther ) OR ( drug dose levels ther )))).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (( drug crest derived ther ) or ((( drug doses level ther ) or ( drug dose levels ther ))))*.