Why tf is Deep Research giving me more vague answers than a normal search? Or am I doing it wrong?

I’m trying to use Deep Research for a very large market research project, but I’m not sure if I’m using it the right way because the results aren’t turning out as expected.

My project is a comprehensive market research document for a skincare brand. I first created a master research document that contains every section I want researched (market analysis, competitors, consumer insights, manufacturing, regulations, retailers, pricing, trends, ingredients, etc.). This master document acts as the blueprint for the entire project.

Instead of asking Deep Research to do everything at once, I split the master document into multiple phases. For each phase, I start a new chat, paste that phase’s sections, and ask Deep Research to complete only those sections while keeping the exact structure and headings from the master document. The goal is to eventually combine all of the completed phases back into one final research document.

The problem is that the output is even horrible than a normal ChatGPT search and it’s driving me crazy. I expected it to be really good but man this is worse and I’m shocked and I’m wondering if I’m doing it the wrong way. Has anyone successfully used Deep Research for a project like this? Is there a better workflow? Please point out where I’m going wrong!!