calc-graph (box), renaming columns in legend

Please, Iam making a graph in calc. I am using data from the first column.
Columns in box graph are a priori named as : 1, 2, 3 , 4, 5

I would like to rename them, according the names in first column of MY TABLE I made graph from.

I used data ranges, as told, but no success.
Please ,can someone help?
Many thanks!