1) Ask a clear question. Being precise in your way to ask will give you more opportunities to get what you ask for
2) You must ask the right person or try to find the right reliable source. Who has the right knowledge and information? Try a research and find the experts on that topic. Today it is very easy to find information on the internet. Lets say you want to do a research to find out which person or website/service that can give you the best tips and advices about: How to beat The Google AdWords Game? You can try to search for this in Google: Top Google AdWords Gurus. On the top of that page you will find a link to Perry Marshall. He is considered as one of the worlds top leading authorities on the Google Pay Per Click System - AdWords. So there you have an expert if that's the topic you're interested in. Or Maybe you ask yourself which are the most popular golf courses in California. Again, visit Google and use the keyword phrase: The top 10 golf courses in California. That will probably give you the result you want.
3) It is important to be well-prepared. You got to have a plan for your questions. If you intend to ask someone face to face it is recommended to practice for the performance. If you follow the steps to be well-prepared the bigger are the chances that you will get your answers. And the answers is likely more accurate and give you valuable information.
4) You got to GIVE something to GET something. For example if you ask a person that give you the answers, you should give some back in the form of appreciation and respect. For example if you visit a forum on the internet and ask questions, you will get a lot of answers. If your questions is thoughtful and prepared you probably get good answers. And if you show your gratitude it will be appreciated a lot.
5) Don't give up. Think of this: Let's say you're new on a topic and want answers so you can build up a foundation of knowledge in that subject. In the beginning you will probably fail and don't find out who to ask or find the right information source on the internet. Remember, the more prepared you are, the better it is. Over time you will perform this better and better. So continue to train yourself.