Assuming your document doesn't use local formatting or character styles, I would try to separate this task into two parts
1. Tag all dialog with a character style (it doesn't need any attributes so this could be formatting-neutral)
2. Search for your term with default paragraph font style

In your example, you could separate the apostrophes from a dialogue close quote by the punctuation that precedes it. If that punctuation is consistent in your document that should work.

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Andrew Lockton
Chrysalis Design, Melbourne Australia