Perhaps you should try some spelling variations:
"covered references conventions" » "covered references connections", "covered referencing conventions", "covered references conversion", "covering references conventions", "overview references conventions", "recovery references conventions"
"layered reference conventions" » "layered reference conditions", "layered reference contents", "layered references conversion", "layer references conventions", "layers references conventions", "based reference conventions"
"ear reference collection" » "ear reference collections", "ear references collection", "ear references collections", "ear preference collection", "fear reference collection"

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: (("ear reference collection") OR ((("layered reference conventions") OR ("covered references conventions")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"ear reference collection\") or (((\"layered reference conventions\") OR (\"covered references conventions\"))))".
• Removing quotes may allow a broader search: (( ear reference collection ) or ((( layered reference conventions ) OR ( covered references conventions )))).
• Adding a wildcard symbol may retrieve word variants: (("ear reference collection") or ((("layered reference conventions") OR ("covered references conventions"))))*.