Well, looks like you are in most of the kills in the games you won and had only a few deaths (lets be real, only a bit more than 4 deaths with over 19 kill pariticpation on average is pretty decent), died a bit more in the ones you lost.... But thats to be expected if you are in most of the team fights..... so chances are its not so much that.
I do see that you play only Sona and Janna pretty much though, and while they are pretty awesome (im partial to Nami myself), they are both always so squishy. Even Nami gets a few more defencive items on average than most squishy supports. This does not go so well if the rest of your team also chooses to have next to no defencive items and/or a tank.
I also see you pretty much have the same build on both of them with next to no variations..... Which if it works its fine, but when it doesnt.... Is there something else that might work better?
My suggestion would be try to find a decent tanky support and practice with them for a bit. Sona and Janna are still going to be there whenever you need them, but just adding that one extra champ or two to your pool could make a dramatic difference. Me personally i play almost every support because i like being a generalist, but i would highly recommend making sure to have at least one tanky support you are comfortable playing.
Also, in normals feel free to try out some builds based on enemy team comp. For example, have you done much with Knights Vow? Pretty nice item to have on Nami or some tanky champ...... How about Zekes Herald? Would work well with both Janna and Sona there, as well as a few other AP supports. Mikeals Crucible perhaps with a heal/shield champ if they have some CC on their team like Ashe? Theres many possabilities.
I did not check your ward score etc, but even with a high ward score you may just need to figure out more optimal places to put them. Have you been clearing wards etc well with your Red Trinket? Been grabbing at least a few Control Wards during the game and placing them well? Stuff like that.
Hope this helps :)