Perhaps you should try some spelling variations:
"could soil book series" » "coupled soil book series", "could still book series", "could fail book series", "could soi book series", "could soil block series", "could soil boron series"
"could soil book studies" » "coupled soil book studies", "could still book studies", "could fail book studies", "could soi book studies", "could soil block studies", "could soil boron studies"
"could sail book studies" » "could fail book studies", "could still book studies", "could fall book studies", "could said book studies", "could bail book studies", "could small book studies"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("could soil book series") OR ((("could soil book studies") OR ("could sail book studies")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"could soil book series\") or (((\"could soil book studies\") OR (\"could sail book studies\"))))".
• Removing quotes may allow a broader search: (( could soil book series ) or ((( could soil book studies ) OR ( could sail book studies )))).
• Adding a wildcard symbol may retrieve word variants: (("could soil book series") or ((("could soil book studies") OR ("could sail book studies"))))*.