To be able to capture these little guys, you probably had to zoom in really close, and that is a problem, the most you zoom, the harder it is to get a focused picture. What can help is the use of a tripod, or try to get closer without using the zoom keep your camera at 50 mm focal length and use the macro function of your camera if you have one. there is a minimum focus distance, if you try to get closer than that, you will not have a clear shot.
If you increases the shutter speed it will help, provided you have enough light... or use a flash
Your camera has some limits, but if you know how to use it, you can probably improve quite a bit before you have to change camera!
You can also post more pictures with specific questions, and make sure your settings are showing.
Enjoy!