If your e-mails aren’t getting responses, then the first thing you need to look at is why you think that may be. The first thing a journo sees is the subject line, make sure that it’s working for you. Look at split testing to find out what works for you.
Think about following up. It could be that in a busy news agenda that your e-mail was missed in the first instance, but after following up the first time, think carefully about following up again.
What about the campaign itself? Is it answering all the who, what, where, when, why and how questions? If you can’t answer those questions, then it’s unlikely that your outreach will be able to do so either.
Improve your chances by triple-checking you’ve got the right journalist, that you’ve got the correct e-mail address and that you’re managing the relationship effectively. Has a colleague already got an excellent relationship with a journalist, ask them for advice, it may even be more appropriate for them to send out the outreach on your behalf.
A successful response rate can depend on a lot of different factors such as news agenda, breaking stories, what’s happening in your client’s niche as well as many others, but you need to be resilient and persistent without being aggressive or annoying.
If you’re happy with the project overall, and believe it should be getting more pickup than you expected then have you outreached to the right people? Have you been outreaching to enough people?