Perhaps you should try some spelling variations:
"the frontiers selection" » "the frontier section", "the frontiers regulation"
"the frontier electron" » "the frontier electronic", "the frontier section", "the other electron"
"the frontiers section" » "the frontier section", "the frontier second"

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: (((("the frontiers selection") OR ("the frontier electron"))) OR ("the frontiers section")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"the frontiers selection\") OR (\"the frontier electron\"))) or (\"the frontiers section\"))".
• Removing quotes may allow a broader search: (((( the frontiers selection ) OR ( the frontier electron ))) or ( the frontiers section )).
• Adding a wildcard symbol may retrieve word variants: (((("the frontiers selection") OR ("the frontier electron"))) or ("the frontiers section"))*.