Hey Melody.. the answer is no.. its difficult at best..
Have a look through this page for a basics of network structure.. then when you do keep in mind that a search is usually only going to make about 8 hops.. meaning get to about 8 other primaries to look for results. There are hundreds of thousands of primary users and so this is not likely to help you find him..
https://www.winmxworld.com/tutorials/wpn.htmlUsing a chat room On WinMX is the best way for him to find you and your files.. not to mention its a great way to enjoy MX even more.. there are lots of great ppl and rooms on the Network that would love to have you and your brother Im sure..
I dont want to brag or nothing but one great room is the WinMxWorld.com Help room.. we dont kick ya out if you dont need help.. or another i like alot is The Music Spectrum great folks but they do ask you have at least 50 files shared and no porn.