yes, Mysql's Full Text index (FTI) will throw away the more common words as it builds the index over time. I believe there's a 50% limit that it imposes by default.
In other words, FTI tends to only save the less common words in the index over time.
Evidently 'Never' and "I've" are too common and that is why you are forced to add more specifics to get hits.
This is off the top of my head and i can look into it deeper, but i think that it boils down to a word ranking algorithm that is in place.
