With the data collected from customers and other sources, distill that information into one-sentence bullets of specific problems. These sentences should be written with respect for the customer perspective. The difference is dramatic. In this example, there may be many other ways to solve the problem of search terms, including changing the size of the edit box. But if you are too narrow, you'll never see the alternatives.
Good engineering is all about understanding the alternatives.
For each problem statement, provide supporting information. Include details about which customers have the problem, how it was reported, and even potential ideas for solutions. Perhaps only a certain subset of users have the problem, or it only occurs in certain situations. Say as much as you need to allow others to confirm or challenge your assumptions. The more open you are about the sources, the less likely people will be to suspect them.