/give multiple items command

According to the Minecraft wiki, there is no way to create multiple types of items using one /give command. You can spawn falling command blocks to achieve a very similar effect, but the command is so long that it can't be started from chat. You might be able to put this command in a command block and use setblock to trigger it.

summon falling_block ~ ~2 ~ {Time:1,BlockState:{Name:"command_block"},TileEntityData:{auto:1,Command:"/give @a diamond 1"},Passengers:[{id:"armor_stand",Health:0,Passengers:[{id:"falling_block",Time:1,BlockState:{Name:"command_block"},TileEntityData:{auto:1,Command:"/give @a gold_ingot 1"},Passengers:[{id:"armor_stand",Health:0,Passengers:[{id:"falling_block",Time:1,BlockState:{Name:"command_block"},TileEntityData:{auto:1,Command:"fill ~ ~-2 ~ ~ ~ ~ air"}}]}]}]}]}