How often has the above happened to you?
Not always, but often enough.
Does it bother you?
It does somehow. Makes me a bit sad and annoyed.
Do you take it personally if people don't respond?
It depends on the topic. If it is just some question or something which has not specifically to do with my own person, then not. But if it is something more related to my person or something which I thought is interesting, then I feel somehow like a small part of me got rejected or considered worthless.
When this happens what do you do if anything to try to get more people to respond?
Depends. If my post is written very long or hard to understand, I might try to make it shorter / easier to read. I would maybe bump up the thread once, but not more than once. If that both doesn't help I have no other chance than living with it.