Serve resources from a consistent URL with gtmetrix

I have facing this issue for a day now.

After checking my site performance in gtmetrix this main problem is on the top of all.

Here is what it looks like
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 525.3KiB.

https://xxxxxxx.com/wp-content/uploads/2015/02/56pxzlduwib8ne1vwx9ws_original.jpg
https://xxxxxxx.com/wp-content/uploads/2015/02/56pxzlduwib8ne1vwx9ws_original.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 511.9KiB.

https://xxxxxxx.com/wp-content/uploads/2015/02/Shopping3.jpg
https://xxxxxxx.com/wp-content/uploads/2015/02/Shopping3.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 131.3KiB.

https://xxxxxxx.com/wp-content/uploads/2015/02/slider2.jpg
https://xxxxxxx.com/wp-content/uploads/2015/02/slider2.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 116.4KiB.

https://xxxxxxx.com/wp-content/uploads/2015/04/121079_P_1405510552741.jpg
https://xxxxxxx.com/wp-content/uploads/2015/04/121079_P_1405510552741.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 59.2KiB.

https://xxxxxxx.com/wp-content/uploads/2015/11/grey-swearter.jpg
https://xxxxxxx.com/wp-content/uploads/2015/11/grey-swearter.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 51.4KiB.

https://xxxxxxx.com/wp-content/uploads/2016/01/x10759000_2.jpg.JrADIJqFAtvERFYuiI-s015Zl.jpg
https://xxxxxxx.com/wp-content/uploads/2016/01/x10759000_2.jpg.JrADIJqFAtvERFYuiI-s015Zl.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 36.2KiB.

https://xxxxxxx.com/wp-content/uploads/2015/02/slider1.jpg
https://xxxxxxx.com/wp-content/uploads/2015/02/slider1.jpg?5e30f7
The following resources have identical contents, but are served from different URLs. Serve these resources from a consistent URL to save 1 request(s) and 1.3KiB.

https://xxxxxxx.com/wp-content/uploads/2013/08/dummy.gif
https://xxxxxxx.com/wp-content/uploads/2013/08/dummy.gif?5e30f7

(domain replaced by xxxxx)

Any help will be appreciated.

Thanks