How to identify a text format in power query

[MohsinBipu]

I have an excel like below. I need to identify a text format (for my case XXX-XX-XX, example 122-22-10). And then I will take that cells including the upper cells.

In the full query, how I can do this? Please find below the Input snapshot and my expected output snapshot. 

[MohsinBipu]

OOhh my GOD.... you are just from out of the world.

Boss How I can learn those things? Any direction is greatly appreciated. 

[wdx223_Daniel]

NewStep=let fx=(t)=>let a=Text.Split(Text.From(t)??"","-") in List.Count(a)=3 and List.AllTrue(List.Transform(a,each _<>"" and Text.Remove(_,{"0".."9"})="")) in Table.FromColumns(List.Zip(List.Accumulate(Table.ToRows(PreviousStepName),{{},{}},(x,y)=>{x{0}&List.Zip(List.Select(List.Zip({x{1},y}),each fx(_{1}))),y}){0}))