Text disappears when I "test movie"

I'm creating a 2 minute animation. In a couple of segments of the video, I have a sequence of bubbles rising from the bottom of the stage to the top. Each bubble has a word or phrase on them. When I play the animation in the timeline, these words and phrases appear, but when I "test movie," they do not show up, i.e., they are not on the bubbles. I thought this may be because each bit of text has to be a symbol or something, but making the text into symbols didn't work. I also can't seem to "break apart" the text when I edit the rising bubble symbol, otherwise I thought that might work.