Importing an engine header file?

Is it possible to import an engine header file so I can use its content in my own c++ classes?

I want to import the FindSessionsCallbackProxy.h file because it contains this struct

USTRUCT(BlueprintType)
struct FBlueprintSessionResult
{
	GENERATED_USTRUCT_BODY()

	FOnlineSessionSearchResult OnlineResult;
};

And my life would be so much easier if I could use this struct in my code. Right now it’s only accessible in blueprint.

I had the same problem when my project was using 4.10.

I upgraded it to 4.11, then i added include as:

#include "FindSessionsCallbackProxy.h"

And then I just added module in MyProjecet.Build.cs like:

PublicDependencyModuleNames.Add("OnlineSubsystemUtils");

And voila! Hope it will help anyone out there. I’ve spent hours before figuring our that the upgrading project to 4.11 was the key. >.>