For many job hunters today, the process of applying for work and trying to get hired can feel like the proverbial “black box” experiment. You send a bunch of resumes out there — including for roles you feel eminently qualified for — but frequently get little to no response, leading you to wonder “What’s going on beyond the curtain? What am I possibly doing wrong? What mysterious factors seem to be getting other peoples’ applications passed through the filter, but not mine?”

This experience is so common today, in fact, I’d actually say that any job hunter who ISN’T experiencing some occasional thoughts along these lines is, well, an anomaly.

So to help people gain a better understanding of how things really work in hiring circles these days, behind the scenes, I recently invited a VP-level hiring manager to come share some thoughts on this topic with a group of my clients. In particular, this individual had faced the need to staff up about 50 new positions earlier this year, within a rapid time frame, and in light of this I invited her to share any insights or takeaways she gained from the experience. Her top tips and advice?

— First, she mentioned that the bulk of the “sourcing” of candidates took place via LinkedIn and that her recruiting team’s primary way to find candidates for the opportunities in question was to run searches on LinkedIn for people with relevant skills, keywords, and qualifications. So if you haven’t already packed your LinkedIn profile with all the relevant language in your field (most people think they have, but usually overlook some important phrases and terminology), make sure to do so!

— Secondly, she said that once they’d narrowed the field down to a short list of candidates and the interview process started, people instantly started to separate themselves from the pack in either a good or bad way. Most importantly, she said she was shocked at how many people (the majority of folks, she stated) had solid resumes, but didn’t demonstrate any real enthusiasm or curiosity about the job at hand — or clearly hadn’t done their homework in terms of boning up on the company, the job description, and the market space in question. So if you’ve just been going through the motions and showing up for interviews without engaging in a crash course of study about the organization in question and its business model, you could be at strong risk of getting screened out.

— Next, when asked what was appropriate in terms of candidate follow-up, she suggested that people send a thank-you e-mail no more than 24 hours after the interview, restating their strong interest in the role and perhaps a few salient reasons why they felt they’d be a great fit. Hand-written cards were a nice touch, she said, but usually took several days to arrive and therefore missed the chance to immediately reinforce any positive impressions of the candidate in the interviewer’s mind.

— Lastly, and perhaps most importantly, when pressed on what the single most critical factor was that led to certain people getting hired/considered versus others, she mentioned that it almost always came down to “little notes” that would be forwarded along from people she trusted, vouching for the credentials/talents of the individual in question. We’re not talking about formal cover letters, mind you, but more along the lines of a quick, informal e-mail or message where an applicant had an existing employee — or mutual acquaintance — take a moment to share some positive thoughts or encourage the manager to give the resume serious consideration.

Commonly (although not always) this might involve a person running a LinkedIn search, finding somebody with a connection to the company, and asking the individual in question, proactively, to put in a good word on their behalf. These little endorsement notes, messages, and voicemails apparently played the greatest role in narrowing down the field of initial resumes down to the short list of ones given most consideration.

So while in some respects it may seem like we’re bludgeoning a deceased equine here, the biggest takeaway of this manager’s observations is that serious job hunters should focus on mobilizing as many people as possible to go to bat for them, make introductions, and sing their praises to employers. However fair or unfair, a “cold” resume alone submitted into an application system will face a significant uphill battle in terms of getting the job done, frequently losing out to those other submissions that come with a warm testimonial or endorsement attached.

So whether this means you need to redouble your efforts in 2016 to engage your existing friends and allies in your search — or bear down and focus on building some new relationships from the ground up — improving one’s networking efforts continues to be the #1 area that active job seekers would be wise to concentrate on. Ask a friend of yours to send a “little note” on your behalf to an appropriate employer, and who knows? This might just be the ticket to your next great opportunity…