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Hmm this is a bit unusual I would say, to keep a DJ since two years and the dreams are still not that vivid…
How long are your entries in general? Do you really pay attention to every little detail and write down all of what you can remember?
Have you tried to make your LD’s more lifelike by asking the dream for more vividness or by rubbing your hands? These are great techniques which show good success. 
Besides this, you could try to mind your senses more IRL, too, like paying heed to what your meal tastes like, how your jacket feels…Eventually your SC will get that you pay attention to this stuff and your dreams should be more vivid.
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Have you ever tried exercising your imagination senses IWL ? If not, I believe that’s what you should do in order to have more realistic dreams: Take some times off, about half an hour around 12:00, lay down and relax completely. Then imagine yourself touching a tree. Feel the rough wood with your hand. All of this should be mentally captured: try smelling, tasting, feeling - not only seeing. That’s what I suggest you should do in order to put your imagination to work, not only in LDs. 
But then again, inside a dream (LDs) everything feels very real, even though after you have woke up you realize it was a bit blurry and unclear - inside the ream it is vivid. Well, with some exceptions of course.
Yeah I know that it can be very hard to write dreams down… 
Maybe you could try to write them down in as much detail as possible for about a week or so and see if you achive any results by this, if it makes your dreams more vivid? Just a thought…
Also, definitely try what Don Anonymus said if your imagination is not that good in general!
Thanks! 