Such a simple question yet so many people hesitate to ask, especially with those outside their inner circle. Overcome your hesitancy by thinking of your request not as a "plea" but rather as an invitation to someone to be a giver. Most people will love helping you and receive a great feeling from doing so.
Someone I had met recently was acting somewhat awkwardly. I asked what the problem was. She told me she didn't want to impose on me with a business question. Impose? I love helping like most of us do.
I see frequently another variation of this same problem Most of us have plenty of weak connections on LInkedIn, the ones you can't remember how you know them. When you find one of your weak connections could be the best person to help you with some quest, reach out. You got everything to win!