Perhaps you should try some spelling variations:
"diseases douglas effectss." » "disorders douglas effectss.", "issues douglas effectss.", "diseases donald effectss."
"diseases drugs effective." » "diseases groups effective.", "diseases drugs affecting.", "diseases davis effective.", "disease drugs effective.", "disease drug effective.", "diseases dogs effective."
"diseases drug effect." » "diseases drug effects.", "diseases drag effect.", "diseases drugs effects."

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: (((("diseases drugs effective.") OR ("diseases douglas effectss."))) OR ("diseases drug effect."))~.
• Removing quotes may allow a broader search: (((( diseases drugs effective. ) or ( diseases douglas effectss. ))) or ( diseases drug effect. ))~.
• Adding a wildcard symbol may retrieve word variants: (((("diseases drugs effective.") or ("diseases douglas effectss."))) or ("diseases drug effect."))*.