If there is one thing I want to ask boldly in an interview, this would be it: Why are you not hiring the ones who have no experience? How can they have work experience then?
I know, the answer is pretty obvious. Nobody wants to hire a greenhorn. Nobody wants to provide months of training to newbies if an employer can just pick the tenured applicants.
So, the reality is, even if you want the job a lot, and your course is related to it, if what you only have is an internship or a practicum, chances are you won't still be qualified.
Another thing is certificate. If you don't have a certificate or a degree, you'll likely to be passed up.
Imagine teaching of English as a Foreign Language, if you are a non-native English speaker, if you don't have a certificate that can back up your English skills, you don't qualify. It doesn't matter if you have a degree in Education.
The funny thing though, if you look White or from an English-speaking country, even if you don't have any degree or TEFL certificate, your English teaching career abroad is already guaranteed.
Does it sound unfair? It does. Yet, the world has never been fair. So, you have to thicken your skin. If somebody rejects you, find another company or organization that will hire you. Invest on those certificates as well. Don't believe those who say you don't need one unless you're going to be your own boss, or you are applying for blue-collar jobs.