Having worked in this area, both as a client and as a consultant, customer understanding is a key to differentiating yourself from your competition.
First a personal belief: surveys are the worst tool to uncover any insights. They are best used to quantify how many do X.
There are a couple of ways we look for insights into customer behavior, and they are both related by fact that you learn by observation.
First is to have your customer demonstrate how they use your product/service, or the product you want to replace, in their normal situation. Ideally you let them run through once just observing what they are doing while taking notes. Then ask them to go through it again where you ask them open-ended questions as they go along. No judgement, just watch and learn.
The second way is to engage them in a serious game, something like the ones we use from Conteneo.co. These are frameworks designed to have the customer create things like the Product Box which encapsulates the key features, benefits, etc. that they are looking for in an ideal product/service like your.
The reason these techniques work well is that the customer is comfortable, they are not being interrogated, and you are cast in the role of the observer, so you're not selling!
Let us know if there's something we can do to help you with this, because it's an important question.

Generally the only reason they would not reveal something in a "regular discussion" is that you're not asking the right things. Try asking open ended questions, such as:
1) "What’s the hardest part about      [problem context]    ?"
2) "Can you tell me about the last time that happened?"
3) "Why was that hard?"
4) "What, if anything, have you done to solve that problem?"
5) "What don’t you love about the solutions you’ve tried?"

People are more comfortable talking to someone like themselves: Don't go overboard, but don't be from another planet.

People are more comfortable talking to someone with whom they have a rapport. Don't just jump right in to questions, ask them some background questions first and maybe give them some of your own background to instill more of a sense of trust and openness.

To glean further 'hidden' insights from them, if you have a software product, you can record their exact on screen interactions via services like Lookback.io That way you can see hesitations, confusion, etc. You could then ask somewhat targetted questions about things you notice in individuals, or things you notice as a common theme across individuals.

If you have a hardware product, you could possibly videotape someone using it for the first time.

If you'd like tailored advice to your specific product let me know,

best,

Lee

Lee is in the right place: live conversations will do far more for you and your target market than surveys (which can be ignored, and have no evidence of heart behind them.)

I've written blog posts and made videos about this question, and just this afternoon answered a client's question about the topic. So the links are handy:

http://www.salestactics.org/?s=pain+points

https://www.youtube.com/watch?v=XBRrHf9WfUc

https://www.youtube.com/watch?v=G1zS8555_14

The prospect has to see that you are genuinely there to help them, first. Then they'll open up a bit. There is a trust hurdle to get over. You can accomplish this simply by saying you something like, "I got into this (their) field because I saw a problem I could fix. It was _____. That's not an issue for you, is it?" That would get the ball rolling.

do a volleyball night with bbq, and treat it as a social event , know your customers and ask them . the solution to change

There are some excellent responses here already so I'll just add this. Customer discovery interviews with your actual customers will help. Customer discovery is part of the lean start-up and business canvas development. A key takeaway in conducting those interviews is to know what your purpose is before starting the interview and then ask "why" five times to each primary question. Each answer to the "why" question will uncover more information, helping you get to the true root of the answer.

Good luck!

You have several options for gathering customer feedback beyond just surveys (although that is a popular choice, as well).

One important thing to remember is that your feedback tool should be timely: You don’t want to wait a few weeks to ask a site visitor if they had a question while they were scrolling through your services list. That opportunity is gone.

Or, if they are reading a few of your blogs, don’t you want to ask them right then and there if they found the content useful, instead of days later when they probably don’t remember? Timing is everything when it comes to getting reliable, beneficial customer feedback, which is why more and more companies are adding pop-ups and live chats to their sites.

We’ve all seen them: pop-up messages or slide-in CTAs that appear as we scroll through an article or open a new page. Why not put these tools to good use and ask your customers a question or encourage them to fill out a survey? You can even offer them an incentive to give feedback like a free downloadable whitepaper.

An even more instant option, live chats are a great way to get the conversation started in real time. While live chats are an ideal outlet for customers to ask you questions, you can also use this feature to send a few their way. Maybe the chat box pops up when they visit your site and asks how they found your business or what they are looking for. It’s like a two-for-one sale where you can improve their experience and collect feedback.

Some other options include holding focus groups and calls. Yes, those take more time and planning, but you'll get plenty of good information.

Once you start collecting feedback, do something with it so you can start to build customer loyalty. And since that's another subject altogether, here are some loyalty tips from a company I work with: http://www.fieldboom.com/blog/customer-loyalty/.

Hope that helps!