This is a peculiar TV show in a way that it was a mix of 20min and 10min stories ("stories", not "episodes").
It either aired a single 20min episode or 2 10min stories episode. But those 2 10min stories were treated as a single episode of The Smurfs with opening and end credits at the beginning of first and ending of second episode.
I see we have all separated which in this specific case probably isn't correct.
Perhaps we used epguides or wikipedia as a source:
http://epguides.com/Smurfs/
https://en.wikipedia.org/wiki/List_of_The_Smurfs_episodes
But it should actually be added more like this...
http://bluebuddies.com/help/smurf_episode_list.htm
https://www.imdb.com/title/tt0081933/episodes?season=1&ref_=tt_eps_sn_1
You should think that single episode is comprised of 1 20min story or 2 10min separate stories, and each individual 10min story isn't a single episode.
So, would it be alright to fix these titles or do we prefer to keep them individual-story-separated like we have them now?