expanding custom column from Html column

Thanks for the reply from ryan_mayu  and lbendlin , please allow me to provide another insight:

Hi, jcastr02 
Could you please let me know if the responses from ryan_mayu  and lbendlin have resolved your issue? If it did, kindly accept them as the solution.
 

ll's response has worked well in my example, and here are the output results:

You may want to take note of the following:

If you are using a custom column approach and directly add the code provided by ryan_mayu  into your custom column, the results in the advanced editor will appear as follows, which may lead to inconsistent output.

 I recommend modifying it to the following:

Text.BetweenDelimiters([NeedtoKnow],".",">",{0,RelativePosition.FromEnd},{0,RelativePosition.FromEnd})

If you wish to retain certain content, I suggest clicking the button in the image below and making adjustments in the advanced editing page:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("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", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Id = _t, LOB = _t, Subject = _t, NeedtoKnow = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Id", Int64.Type}, {"LOB", type text}, {"Subject", type text}, {"NeedtoKnow", type text}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each Text.BeforeDelimiter(Text.AfterDelimiter([NeedtoKnow], ">"), "<")),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Custom"}),
    #"Added Custom1" = Table.AddColumn(#"Removed Columns", "Custom", each Text.BetweenDelimiters([NeedtoKnow],".",">",{0,RelativePosition.FromEnd},{0,RelativePosition.FromEnd}))
in
    #"Added Custom1"

Please find the attached pbix relevant to the case.

Of course, if you have any new discoveries or questions, please feel free to get in touch with us.

Best Regards,

Leroy Lu

If this post helps, then please consider Accept it as the solution to help the other members find it more quickl

Then you need to provide more sampele data, since the logic I used do not work for your real data.