Here is a new site helping with the Facebook graph search queries – Who Posted What (Idea by Henk van Ess, Developed by Daniel Endresz,) The site (still in Beta) offers to search for comments by a user with a given keyword or posted within a certain date range. The Facebook ID that is required can be easily found via https://findmyfbid.com/.
Apparently, the template string to search for somebody’s posts with a keyword is –
https://www.facebook.com/search/<FB ID>/stories-by/str/<keyword>/stories-keyword/intersect
Now, if you wanted to find comments containing a given keyword by a certain person, the template, similarly, can be, as I have discovered –
https://www.facebook.com/search/<FB ID>/stories-commented/str/<keyword>/stories-keyword/intersect
I find these searches helpful in locating posts and comments from given people on given topics of interest.
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