Like so many things in application design..the end result may seem simple (you click an area and it gets filled with colour) but the means to accomplish it are not.
Read through the article and figure out what you can, if you need us to clarify parts of it then tell us which parts you dont understand and we'll try to explain them.
There isnt a simple, pre-written method that you can use for this. You need to write code that will figure out the area you want filled, determine the edges of the area, etc.
Dim Adapter As New OleDbDataAdapter
Dim Command As New OleDbCommand
Dim xFrom As String = dtpFrom.Value.ToString.Substring(0, dtpFrom.Value.ToString.IndexOf(" "))
Dim xTo As String = dtpTo.Value.ToString.Substring(0, dtpTo.Value.ToString.IndexOf(" "))
sqlQuery = MainQuery ...