You've sent out numerous applications with no interview invite and fewer regret emails.
Here are a few reasons why you may not have been shortlisted.
Technical requirements - Contrary to popular advise to apply far and wide regardless of the lack of academic requirements, employers are interested in candidates that have foundational knowledge for the role that they need to fill. This translates to reduction in upskilling costs and time to bring recruited candidates up to speed. For instance, if a role requires a candidate with a degree in HR, those with other specializations need not apply.
Missing information - check that you've included all pertinent details in your CV. This includes your contact details, academic and professional qualifications, your degree honors, high school certificate details especially where the advert indicates a minimum grade requirement, relevant work experience quoting the period between which you were at each organization.
Failure to customize your CV - using one version of your CV to apply for all roles. Make the recruiters work easy by highlighting skills and experience that makes you an ideal fit for the role you're applying for as opposed to subjecting the recruiter to a game of search and retrieve.
Formatting and grammar mistakes
Use a simple format that outlines your qualifications, work experience, skills and interests. Grammar mistakes indicate laxity or carelessness as opposed to attention to details, an attribute required to deliver excellent work for any role.
Aim for an ATS friendly CV. Some recruiters use Applicant Tracking systems that shortlist profiles based how well they match the key words from the job description.
This calls for a simple format avoiding tables, columns and graphics, using standard section headings and key words from the job description to increase chances of your CV being shortlisted for roles applied for.
Note: ATS are unable to read graphics and content in columns.