Perhaps you should try some spelling variations:
"frequency networks. historical survey" » "sequence networks. historical survey"
"science network. historical survey" » "sciences network. historical survey", "science networks. historical survey", "science work. historical survey"

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("frequency networks. historical survey") OR ("science network. historical survey")).
• Removing quotes may allow a broader search: (( frequency networks. historical survey ) or ( science network. historical survey )).
• Adding a wildcard symbol may retrieve word variants: (("frequency networks. historical survey") or ("science network. historical survey"))*.