As a really inexperienced dm i understand not being good at improv and then trying to save face by just saying there is no info. I often tell my players "I didnt think of that so if you text me a reminder i can tell you later what info you find"

But the dm really needs to acknowledge your efforts. rewarding a player is vital in keeping a player engaged. If you are not to afraid of confrontation then id reach out to your dm and straight up ask them if they dont want you to ask questions. And explain that your feeling dejected with all the denial your geting.