How do i filter the Data From datatable using the Extracted String From PDF File

You can try to enhance the filtering by e.g. Trimming / Harmonizations

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dtFiltered =

(From d in dtData.AsEnumerable
Where d("Client Name").toString.Trim.Equals(searchNameVar)
Select r =d).CopyToDataTable

Handling empty filter results we can do:
:ambulance: :sos: [FirstAid] Handling of The source contains no DataRows exception - News / Tutorials - UiPath Community Forum

can you tell / show more?