Perhaps you should try some spelling variations:
"rescue research theories" » "rescue research theory", "rescue research themes", "rescue research topics", "residue research theories", "rescue search theories", "resource research theories"
"resident research series" » "residents research series", "president research series", "residency research series", "resident research services", "resident research service", "resident research summaries"
"resident research studies" » "residents research studies", "president research studies", "residency research studies", "resident research study"
"tissue research series" » "issues research series", "pressure research series", "disease research series", "tissue research services", "tissue research service", "tissue research summaries"

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: (((("tissue research series") OR ("rescue research theories"))) OR ((("resident research series") OR ("resident research studies")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"tissue research series\") or (\"rescue research theories\"))) or (((\"resident research series\") OR (\"resident research studies\"))))".
• Removing quotes may allow a broader search: (((( tissue research series ) or ( rescue research theories ))) or ((( resident research series ) OR ( resident research studies )))).
• Adding a wildcard symbol may retrieve word variants: (((("tissue research series") or ("rescue research theories"))) or ((("resident research series") OR ("resident research studies"))))*.