I have run a couple of campaigns with a few of my friends, and these people are genuinely interested in Dungeons & Dragons.
However, no matter what I do, they will not focus on the story, instead treating it like some sort of slaughter-fest. They do not really kill everything that moves, which is good, but they miss nearly everything in the game because they just fail to interact with it. The only way we have completed campaigns is through me pretty much telling them OOC what to do and where, because they are that lost.
Now, I have read this question ("How can I deal with players who don't consider the narrative?") but it does not seem to answer my problem, as I am posing no challenge nor puzzle. They just fail to pick it up. I am the GM and I have tried to help them in every way I can imagine, but it just does not seem to work. I do not think it is me being a bad GM, because I have played with other groups and that went just fine. Short of telling them "There is a quest here, you should go here and talk to Joe there" what could I do?
For some possibly helpful information, or to just save time, I have tried having NPCs talk to them and hint at so-and-so having a job for them, I have tried having them find letters with a name on it and a note with the start of a quest on it, and they just shrugged and left. I cannot make it any more obvious, and it is starting to affect gameplay, as we are playing one of the official campaigns, with just a little bit of homebrew added (just a bunch of other quests that add some extra leveling up opportunities and loot opportunities).
It's not that we haven't talked about what kind of game we're playing We have actually held several "session 0's" and we do talk about story. We hold an end session around 10 minutes to the end of our game time, and we talk about each other's expectations. One PC is borderline murder-hobo, and he does express his interest to pretty much kill the biggest, baddest thing around. The character is also extremely touchy in game, and will blow up at the slightest insult. However, thankfully, that is only the PC, not the player, and we do all realise that it is just a game. One of the other players just seems... not really willing to contribute to the betterment of the group. We are a band of 4 people.
Short of railroading them, what can I do to get them to focus on the story and pick up on story hooks?
Answers should demonstrate experience or citations per What are the citation expectations of answers on RPG Stack Exchange? and not just be unsubstantiated opinion. What have you done or seen done to address this issue?