Google Sheets as a data source - filtering

Hi. I started my Grafana explaration recently and as such started easy - using Google sheets as a source. I finally managed to get the sample graph working (date was read as null so had to do a UNIX conversion trick which I don’t like but that for another post). As the report is quite large (A:AI columns) I linked all hoping to pick up some of them to be displayed. I can’t find how to filter out irrelevant to my needs coluns for the time being. Later on, I won’t be able to touch the final sheet as it is auto populated and I have read only access. I would like to avoid making a new sheet to query master for just some data as that sounds to me as unnecessary workaround.
Any suggestions?