I had vaser lipo on 4 areas in January and they took under 2L out. Why can't I see any difference?

Hi, please be patient as improvement will continue for 4–6 months as swelling and irregularities resolve. These contours can even improve throughout the year after surgery. 
For your guidance, if you had loose, sagging, or inelastic #skin before the procedure, these are problems which would tend towards poor results in liposuction. In fact, these problems may be worsened and may be best addressed by other procedures such as a leg or body lift (e.g. tummy tuck) in conjunction with #liposuction. Excess skin would usually shrink back over the area of the body, but please take note that liposuction is used to reduce volume not tighten skin. There are non surgical devices such as #ThermiSmooth radiofrequency and #VelaShape3 to help tighten skin after liposuction for patients who will benefit from this additional care. 
It is best to strictly follow the prescribed aftercare for best results and do not hesitate to contact your surgeon if #revision is an option. Best of luck! 
#RealSelf100

It is really impossible for anyone to make a reasonable comment on this without photos and over the internet.  You are best served by returning to see your surgeon and making sure that after photos are taken so you can compare to your before photos.  It can also depend on what you mean by 2L--were 2L of fat removed or 2L of fat + fluid removed.  If the 2L was the total amount of fluid/fat removed, up to 2/3 of that may represent fluid and only 1/3 actual fat.  If it was 2L of fat removed you should see a difference and will probably be able to tell when you look at the pictures and compare to what you had before the surgery.  Sometimes it is difficult to see it when we look at ourselves in the mirror everyday but when we put the before/after side by side the difference becomes apparent.