Facebook Graph Search will now allow searching for posts, status updates, photo captions, check ins, comments etc. You can do so by including the word "Posts" and adding your desired search phrase in it accordingly.
Some examples are shared below-
Posts about my birthday party with my friends
Posts about dancing with the stars by my friends
Posts about my pet playing with my dad
Posts I Commented On
My Posts from Last Year
Graph search is available only on the US English version so users from other country will have to wait until they can see this feature working for them.