Perhaps you should try some spelling variations:
"heir apparent" » "huir apparent", "her apparent", "weir apparent", "heir apparently", "heir aparente", "heir apaparente", "heir apparental"
"heir apparental" » "huir apparental", "her apparental", "weir apparental", "heir apparentlyal", "heir aparenteal", "heir parental", "heir apparently", "heir aparentan", "heir apaparenteal", "heir apparentalal"
"heir aparentely" » "huir aparentely", "her aparentely", "weir aparentely", "heir aparente", "heir apparently", "heir aparentes", "heir aaparenteely", "heir aparentalely"
"heir parent" » "huir parent", "her parent", "weir parent", "heir aparente", "heir parental"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"heir apparent\") OR (\"heir apparental\"))) OR (\"heir aparentely\"))) OR (\"heir parent\"))~".
• Removing quotes may allow a broader search: (((((( heir apparent ) OR ( heir apparental ))) OR ( heir aparentely ))) OR ( heir parent ))~.
• Adding a wildcard symbol may retrieve word variants: (((((("heir apparent") OR ("heir apparental"))) OR ("heir aparentely"))) OR ("heir parent"))*.