First, make sure "Replace straight quotes with Smart quotes" is checked, on
the "AutoFormat As You Type" tab under Tools | Autocorrect Options. Then
replace " with " (all the quotation marks with tehmselves), which will
replace any straight quotes in the document with smart quotes.
Now do your wildcard Find/Replace
In the Find What box, your text needs to be:
(")(*)(")
Note that your quotes MUST be smart quotes! I usually copy them from the
document and paste them in to the Find What box
Your Replace with text needs to be:
\2
and while your cursor is in the Replace with line, select the Format button
(if you don't see it, click MORE and then the Format button) Select Font and
choose BOLD
Make sure Use wildcards is checked and Replace all
FYI...you may end up with a few left over opening smart quotes which you can
remove by finding the Opening smart quote (remember, copy from the doc) and
replacing it with notihing (make sure to turn off the formatting in the
replace box by clicking the No Format button).