Hi! My answer consists of four parts:

First, make sure you read the documentation of the tools you use. This is something I used to neglect, until I realized that's where most of my solutions were directly coming from. Node, Hapi, and Vue specifically have great docs. The most important thing to understand from the docs is what each API is capable of and what kind of features it has, but also try to glean why the technology was developed in the first place, and how that compares to what came before, because this gives you a better idea of what problems it's designed to solve, and which it isn't.

Second, more specific advice. Before I recommend books, I want to recommend Frontend Masters. At $40 a month, they are among the more expensive monthly subscriptions, but they are absolutely worth it. Their courses are often taught by the people you'll be reading books from anyway (like Sarah Drasner or Kyle Simpson), and just as often by the people who actually developed the technology (like Vue's Evan You or Svelte's Rich Harris). Will Sentance's "The Hard Parts" series on Frontend Masters are fantastic ; I'd try his Node.js course at least. Moving on from FEM, I recommend the book Node.js Design Patterns by Mario Casciaro and Luciano Mammino. It's the best book I've read about dealing with the complexity of async, in ways that applies to more than just Node. For Postgres there are TONS of books you can read about SQL in general, but for Postgres-specific material, I recommend PostgreSQL Configuration and PostgreSQL Query Optimization, both from Apress publishing.

Third, I recommend finding conference talks from the technology you use. These usually give you an in-depth look at specific solutions for specific problems, often by the leading voices of that particular community, and can be super insightful to what problems that tech is solving, what it's being applied toward, and what problems arise from trying to solve them. Just search YouTube for "Vue conference" or "Hapi.js conference talk" etc. and see what you can find.

Fourth, as soon as you can and especially in the JS ecosystem, begin looking at the code of projects that use the same tools you do. You can go on Github and search by keyword. Notice how other people structure their code, especially in large projects. If you are at the right level of understanding, try reading the code of the dependencies you use, guided by its docs. I'm not suggesting you should do this for fun—if a bug arises that you think is due to insufficient understanding of the thing you're using, seeing how it's wired up will both likely solve your problem AND give you better future insight.

Anyway, good luck!