Hello, sorry for the late reply.
Actually we have several music programs, since you have not specify you used software, it is difficult for me to offer the suitable suggestions. However, we tested the function and found the search results are mainly MP3, HD audio, WAV and etc. So, if you could offer me more info about the software and your operations, I could do more related study about it.
Thanks for your feedback. It is true that the build-in search engine of our program does not have the filter function currently. We will try to optimize the this function in the future.