Perhaps you should try some spelling variations:
"diseases drag effect." » "diseases drug effect.", "diseases drugs effect.", "diseases dr effect.", "diseases drag effects.", "diseases dag effect.", "diseases dung effect."
"diseases dna effects." » "disease dna effects.", "diseases donna effects.", "diseases dhea effects.", "diseases data effects.", "diseases cla effects.", "diseases sea effects.", "diseases a effects.", "diseases ia effects.", "diseases kra effects."
"diseases dna effect." » "disease dna effect.", "diseases donna effect.", "diseases dhea effect.", "diseases a effect.", "diseases ia effect.", "diseases kra effect."

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 dna effects.") OR ("diseases dna effect."))) OR ("diseases drag effect."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"diseases dna effects.\") OR (\"diseases dna effect.\"))) or (\"diseases drag effect.\"))~".
• Removing quotes may allow a broader search: (((( diseases dna effects. ) OR ( diseases dna effect. ))) or ( diseases drag effect. ))~.
• Adding a wildcard symbol may retrieve word variants: (((("diseases dna effects.") OR ("diseases dna effect."))) or ("diseases drag effect."))*.