LG G3 picture in internel memory missing in gallery

So this happened after my phone shut down ( low battery LG G3 ) my gallery was almost empty... all i can see picture saved on my SD card and there was a sign on the top right corner that it was on the SD card ( sd icon ) so i go to file manager and find all my whatsapp picture and other saved picture on my internall memory... but its really hard to find a specific pic this way...

So my question is:

How can i see the picture again in my gallery ?

Thanks, Sharbel sassine.