@burcidi-- Like the article said, dark urine with a strong odor means that your urine is very concentrated. This is not good because it shows that toxins are staying in your body longer than they need to. You need to drink more water to eliminate these toxins regularly.
Ideally, urine should be a very light color, almost clear and it shouldn't have a strong odor. You should drink more water until you see this with your urine.
It's normal for urine to be slightly darker and with odor in the morning since most of us don't drink water at night. This might also be the case if you're taking medications because those are excreted through urine as well. Try and drink more water during the day to make up for it.