Can anyone offer some help? My ROI (-0.86) and Win % (5%) are terrible

Here are my selections, contenders and results for the races I bet on tonight.
R1 3,2 Contenders 4,3,2,2B,1 Results
R2 5,7 Contenders 3,5,7,2,4 Results
R3 6,8 Contenders 3,8,2,7,6 Results
R4 Passed
R5 6,2 Contenders 3,4,6,7,8 Results
R6 1,4 Contenders 4,1,8,6,5 Results
R7 3,6 Contenders 9,3,5,8,2 Results
Kisha