The following commands are provided:
/find <text> - Find lines containing <text> and scrolls to them. Repeat command to find additional occurrences of <text>
/findall <text> - List all lines containing <text>
So for example i want to see what all people are trying to sell, so I type "/find WTS", and it will scroll backwards to the most recent occurance. I can then repeat the command to find additional occurrences.
If instead i just want to see the lines containing my search in a list i can use "/findall WTS" and each line containing "WTS" will be printed.
I haven't tried, but I believe you can use the full Lua pattern matching syntax in case you want to do something more advanced.