All my inventory disappeared except my armor when I died in a realm

I was playing in a world with my friend and he killed me, when I respawned and went to get my things, the only thing that remained was the amor, all the rest of my inventory disappeared (diamond sword, 3 iron pickaxes, 3 blaze sticks and a potion against fire), I immediately killed him thinking that he would have my things but he had nothing. 

I hope to recover those items that are the most important

I don't have a picture of all the pickaxes, the potion or the blaze sticks because it was unexpected and I didn't think my things were going to disappear.