If your S.G. is still close to what it was when you started your ferment, then you have a problem such as a stuck ferment. You TYPICALLY see a drop almost by 2/3 within 5-10 days from the time of pitching the yeast. Though some yeasts are fast fermenters and will ferment to dry in 3 days, so much does depend on the yeast and the temperature.
You want the ferment to cause the S.G. to drop, meaning as the number drops there is alcohol being produced from the available sugar. For example: if your starting S.G. (also documented as O.G.) is 1.090 and your final reading (also documented as F.G.) is 1.008 (you've checked it every day for 3 days and there is no change at all), then you can calculate your actual ACV (or if you really want this wine to be dry, you could try to tackle this as a stuck ferment and see if you can get the ferment to resume). I personally like this site to calculate my potential and actual ACV: http://dd26943.com/davesdreaded/tools/convert.htm
If you want a low alcohol content wine then you need to know what your starting S.G. should be for the ACV you desire, based on the assumption that the wine will ferment to dry. What was your starting S.G. and what day did you pitch the yeast, temperature of ferment & what yeast are you using.