Perhaps you should try some spelling variations:
"heir apparent" » "huir apparent", "her apparent", "weir apparent", "heir aparente", "heir parent"
"heir apparently" » "huir apparently", "her apparently", "weir apparently", "heir aparentely", "heir parently", "heir apparental", "heir apparent", "heir apparente"
"heir apparente" » "huir apparente", "her apparente", "weir apparente", "heir aparentee", "heir parente", "heir aparente", "heir aparentes"
"heir parently" » "huir parently", "her parently", "weir parently", "heir parental", "heir parent", "heir parente"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("heir apparent") OR ((((("heir apparently") OR ("heir apparente"))) OR ("heir parently"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"heir apparent\") OR (((((\"heir apparently\") OR (\"heir apparente\"))) OR (\"heir parently\"))))".
• Removing quotes may allow a broader search: (( heir apparent ) OR ((((( heir apparently ) OR ( heir apparente ))) OR ( heir parently )))).
• Adding a wildcard symbol may retrieve word variants: (("heir apparent") OR ((((("heir apparently") OR ("heir apparente"))) OR ("heir parently"))))*.