Curiosity about a culture is welcomed almost everywhere when it arrives wrapped in humility rather than judgment. The framing that works: ask from a position of wanting to do things properly, such as asking what the right way to behave at a ceremony is, or what a tradition means to the person, rather than framing anything as strange or asking why locals do things so differently. Questions that invite someone to teach are flattering; questions that ask someone to justify are not.
Timing and audience matter. Save deeper cultural questions for people you have some rapport with, a colleague, host, or friend, rather than strangers mid-transaction, and one-on-one settings beat groups, where a question can put someone on the spot. Follow their energy: if an answer is short or the subject shifts, let it go gracefully. Steer away from framing that ranks cultures or draws comparisons with your home country, and be delicate around religion, politics, and painful history unless the local person opens those doors first.
A few phrases carry you far: asking what something means, how you should do it, and whether you got it right afterwards. Showing that you acted on previous answers, wearing the right thing, greeting the right way, is the strongest signal of all, and it typically unlocks warmer, deeper conversations than any question could.