Because the store doesn't have a specific way of just showing the apps by a specific publisher, the option available is to search. As you've discovered there's no way to hint to the search that the term provided is a publisher name it may pick up other things too.
One hack I have seen used is to add custom keyword on all the apps by a publisher that is far more likely to be unique and searching for that. Something like "apps-by-code-beside". The search currently picks up keywords and a value like this is unlikely to show up other apps.
As an alternative, you may be able to provide a better experience by directing people to apps listed on your own website. This could contain appropriate links to the specific apps in the store. As a publisher has more and more apps it becomes less likely that all will be relevant to the person using one of them. It may be more appropriate to show only the relevant apps(relative to the obe being used) linked directly to the store. Yes, this can be more work but it provides you, the publisher, with greater control and, hopefully, the people using the apps with a better experience.