The part of your chart that you labeled "chart draw" is controlled by the chartArea
option:
chartArea: {
top: 25,
height: '80%'
}
Each sub-option (height, width, top, left) can be either a number (pixels) or a string (percent of total chart height or width). Use these options to enlarge the chartArea's height and/or shrink the area devoted to the chart title.