Translation:They are searching for a bunny. Maybe the bunny is over there.
That is because of the way the articles work English. At the beginning, you don't have any idea of the bunny used in the sentence, so it'll have "unclear" article "a", and in the latter sentence the same bunny is referenced again so this time around it'll have the "clear" article "the". And I started with "the" in this comment, as it is already clear from the context that I am referring to the bunny used in the sentence we are discussing about.
I know some linguists have argued that there is the subject in expressions like there are those who say... or there is a bunny in the box. The more straightforward explanation is that this is an adverbial expression and the subject is the noun phrase that immediately follows the verb. This was certainly the case historically. It is certainly the case in analogous expressions -- there stands the old castle, there remain several things to discuss, yonder lies the grave of my grandfather, here comes everybody. I guess an argument for there sometimes being a subject is that in some dialects, not mine, the verb is always singular rather than agreeing with the following noun phrase in number. This seems like a thin reed to hang anything on. I don't recall what the other arguments are, but I think they are all theory-internal: "our theory requires that this be an NP, not a locative adverbial".
Same for me, really tired of these small details getting wrong.