Perhaps you should try some spelling variations:
"heir apparent" » "her apparent", "hair apparent", "herr apparent", "heir apparently", "heir apparental"
"heir parent" » "her parent", "hair parent", "herr parent", "heir parental"
"weir apparent" » "weir apparently", "weis apparent", "wei apparent", "weil apparent", "weir apparental"
"huir aparente" » "huir aparece", "huir aparentale"

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 ("weir apparent"))) OR ("huir aparente"))) OR ("heir parent"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"heir apparent\") OR (\"weir apparent\"))) OR (\"huir aparente\"))) OR (\"heir parent\"))*".
• Removing quotes may allow a broader search: (((((( heir apparent ) OR ( weir apparent ))) OR ( huir aparente ))) OR ( heir parent ))*.