take a counter and fetch the value of the cells in datatable and compare against the desired value, increase the counter for every match.
Code:
col_count= Browser().Page().WebTable().ColumnCount(1)
row_count=Browser().Page().WebTable().RowCount
'counter
cell_count = 0
For irow=2 to row_count
For icol = 1 to col_count
If trim(Browser().Page().WebTable().GetCellData(irow,icol))= "data to be searched" Then
cell_count = cell_count+1
End If
Next
Next
msgbox cell_count
