Concrete is a naturally very porous material and water can rise up or travel through capillaries which can lead to damp floors and mould issues.
Rising damp under carpet.
Rising damp also known as salt damp or salt attack is a natural phenomenon where salty ground moisture rises by capillary action up a brick or masonry structure such as a wall or a fireplace.
The common causes are a missing damp course or the deterioration of the damp course layer due to age.
Concrete s porous nature means that water from under your home can seep up through your concrete floor making it damp.
The easiest problems to isolate and repair with damp floors are issues with above ground services such as leaking pipes.
This is less common in new buildings as damp proof membranes are required at the initial construction phase to prevent rising damp.
This can cause issues with mold and mildew especially if you have carpet or.
Damp rising through concrete floor slabs is fairly common when a damp proof membrane has failed or was not installed before the floor was laid.
Fixing the damp proof membrane.
You also mentioned that there are vinyl tiles over the floor.
Assuming that the damp proof membrane dpm under the concrete has failed in areas then yes you possibly would get the odd patch of dampness showing in the floor.
It becomes a problem when the moisture levels are too high and water is transferred to the finishing layer above.
If your property is suffering from rising damp which then rises through to the surface of the concrete then this is a more complicated procedure to fix.