Well, It depends on the relationship between you and person that you gonna ask some good weird questions. If the person is your closest friends or same gender you can simply ask anything, right? But, the person is not your friend or not even the same gender then, you need to be careful.
Asking weird questions do not guarantee that you will know that person well. You need to familiar with that person. Start with soft and formal talk, and listen to them carefully. If you only listen to them, you will know far more than just asking weird questions. Make sure that your questions do not spoil your personality for that persons. Sometimes, If you ask about their basic interest, what kind of food or drinks they like? what kind of movies or Youtube videos they watch? and what kind of article or magazine they read? These kinds of simple questions help you to know them better.
Last but not the least, Always remember to listen to them carefully and ask according to the flow of conversation that you are doing. Good Luck, You will know them better. Don't forget to smile! :)