NEW YORK (MainStreet)—High unemployment, especially for young people, has become a staple of the economy over the past half-decade, but what exactly is behind it? The common answer to that question is simple mathematics: the economy has yet to recover the more than 8 million jobs that were lost during the Great Recession.

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Yet, this explanation only tells part of the story. It fails to touch upon the scores of employers practically begging for new hires to fill openings to no avail. According to the Bureau of Labor and Statistics, there were 3.9 million unfilled job openings in the end of June.

What's worse is that nearly a third of these jobs will likely go unfilled for over three months, according to a recent survey conducted by CareerBuilder.com. This void represents a great deal of untapped potential that would make a difference to the economy if unleashed.

The problem is not simply that many jobs didn't return or that they were eliminated by technology - though both are contributing factors. A big part of the issue is that there is a disconnect between those looking for work and the needs of those hiring that has yet to be bridged.

The root cause of the divide has been up for debate, but many have suggested it is the result of a skills gap – the difference between the skill-sets the unemployed possess and those required by available jobs.

The Business Roundtable recently conducted a survey to determine the extent to which workforce training gaps and skill shortages are a problem, and to identify the specific areas in which training and skills gaps exist in the U.S. workforce, according to Siemens CEO Eric Spiegel.

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"The study found that currently engineering, information technology, data analytics and skilled trades present the biggest skills gaps, and these gaps are expected to persist for at least the next five to ten years," he said.

Surprisingly, some of the skillsets that employers are looking for aren't so much technical, but interpersonal. According to a recent survey conducted by Express Employment, 69% of employers view soft skills as more important than hard skills, with 65% of employers reporting reliability and dependability as the most important trait of a good employee.

Another cause of the supply-demand imbalance is a persisting stigma towards blue-collar jobs. Many people simply believe that certain jobs are "beneath them" and simply aren't interested.

Krystal Wells, owner of Portland, Ore.-based cleaning service The Other Woman, recalls how difficult it has been to find good workers to join her staff.

"I have gone as far as contacting over 400 different individuals that I took the time to read their profiles to see if from what I read they would be a fit and custom pick the people who most fit this job to call," Wells said. "After all the people I contacted, I had one person that was interested and never showed up to the interview."

So how exactly do we solve this issue? What can we do to connect new and unemployed workers with available jobs in these industries?

Many believe that the key to solving this problem begins with workforce training. To that end, the U.S Department of Labor is currently requesting $6 billion to be used toward training and employment programs, but employers and educators have an important role to play in this as well.

For starters, employers must make a more concerted effort to train current workers to fulfill more advanced roles in their firms. We also need more from our institutions. Our schools must do a better job helping students cultivate the skills required for jobs in this new economy.

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"If soft skills create the largest skills gap between employers and job seekers, we shouldn't be afraid to question why post-secondary schools focus almost exclusively on hard skill development," said David Lewis, vice president of franchising for Express Employment Professionals.

Solving this problem will also require a change in our thinking towards careers in certain industries. Jobs in the manufacturing sector, for example, need to become more attractive career paths for young people. Spiegel, the Siemens CEO, believes that working to change this perception will help people to see the wealth of opportunities available in these professions.

"Today in the U.S., there is a bias against jobs in the manufacturing environment," Spiegel said. "We need to create an environment of respect around skilled technical work. We need to make people aware of what the Commerce Department reported in 2011: people in STEM fields—that is, science, technology, engineering and math fields—can expect to earn 26% more on average and be less likely to experience job loss than non-STEM occupations."

--Written by John Okoye for MainStreet