You: Yes, I'm a qualified plumber and can do the job.
Recruiter: Sure, but can you fix our pipes?
You: Off course, that is is what I was trained to do.
Recruiter: You keep saying you're a plumber but we need someone to fix our pipes
You: I can do it.
Recruiter: we need someone who have worked with pipes.
You: I have worked with those.
Recruiter: Sure, but we need someone to fix our pipes.
etc