If you're applying for jobs either online or by other means available to you and you're getting little or no response (notwithstanding applying for jobs is the least effective way to get hired), the lack of overall response by employers is a valid red flag that your resume is not doing its job.
The primary purpose of the resume is to get your foot in the door. Given that you are pursuing positions that align with your knowledge/skills/experience, if doors are consistently not opening it means the message of your resume is flawed. Here are the most commonly recurring blunders made by unwitting job seekers:
Shoddy page formatting: Remember, the resume is a visual presentation as much as a content document. As such, it needs to draw the reader in much like a brochure or advertising piece. It is, in fact, an extension of your visual brand.
The disorganized header, irregular margins, sloppy line spacing, distracting page borders and multiple font styles (in the name of "standing out") will bring your resume to a visual deadlock. Haphazard formatting of your resume creates an amateurish effect. The hiring manager isn't looking for an amateur.
Including an objective statement: The problem with the objective statement is that it's all about what you want. Employers have no vested interest in what you want. Their focus is their own need as a company. Consequently, the objective statement on the resume has been replaced by the Summary/Profile. Don't misunderstand...you need a job objective; just don't put it on your resume. (The exception is including it on a functional resume when pursuing a change of career.)
Lifeless summary/profile: Interchangeably known as the Summary or Profile, it is this 3-5 sentence power-house narrative that induces the employer to read further. What is it that you do especially well? What are you known for? What differentiates you from others in your profession? The Summary/Profile is your brand message.
Task focused vs. accomplishments-driven bullet points: When you consider that the hiring manager knows what the job entails, why are you sending a resume that’s nothing more than a job description? The information within each of your positions needs to effectively convey the impact you've made within each role.
Job seekers struggle with the idea of "bragging" in the resume. You're not bragging when you deftly convey your influence within companies throughout your career. Employers expect you to market yourself. That is, after all, the purpose of the resume. To not do so diminishes your value in the employer's eyes.
Your resume is your sales brochure promoting a product...you! With that in mind, consider that the value of an effective sales message is measured by the interest generated in the buyer. With the glut of people out there who do what you do, the message of your resume needs to rise above the level of simply average. Indeed, the employer doesn't have to settle for average in today's buyer's market.
Constantly ask yourself "So what?" while crafting your resume to move it towards a powerful marketing tool that gets your foot in the company door.