Need to filter for a specific pattern

[wilster98]

I am trying to extract data using power query, I'm very new to Power BI. Power Query is enabling me to pull data from closed files, in individual folders. Now I need to fine tune the query. All of the filenames start with a specific pattern then what ever description is needed. I need the pattern without the description. The specific pattern I am looking for is ###-#####_Alpha######## (e.g 555-5555_C55555555). Is there a way to do this. I tried the text filter but It only got me so far. Any help would be appreciated.

 

[alansidman]

Show us a sample of your data and the mocked up results for the raw data. Use XL2BB to upload your data.

 

[wilster98]

My file is huge and has proprietary information. I can add a snap of the problem. the data that I need follows a strict naming convention. The highlighted file name is the pattern I need to filter for