Veins increased and worse on thighs and back of calves after sclerotherapy. (Photos)

From the pictures posted, there appears to be a combination of small spider veins, some matting (this is enlargement of smaller tiny red veins after sclerotherapy or other procedures as a result of inflammation and dilatation of the tiny vessels) and a bit of hyperpigmentation or brownish discoloration. 
I think you need more sclerotherapy with a different sclerosant agent not prone to cause matting such as 72% glycerin or chromated glycerin.  Keep in mind you only had 2 sessions a full year apart. Spider veins generally take several treatment to fully go away.  In addition to this, it may necessary to do an ultrasound evaluation to assess pressure from larger internal veins resulting in the exterior veins becoming more visible.  I recommend you see a vein specialist for a more complete evaluation.

If you have any underlying issues with your circulation, it may cause more spider veins or spider vein complications (matting). Sometimes small feeder veins need to be injected using ultrasound as well. Surface lasers don't do as well as we'd like for these kinds of veins.

The posted pictures look like small spider veins and staining post sclerotherapy. Staining is a difficult problem to treat and usually improves over time (I have seen this take 2 years).  Some staining may not improve. You basically have 3 choices for your veins:  leave alone, sclerotherapy or topical laser.  I would recommend seeing a vein specialist for a full venous evaluation including a venous ultrasound to look for underlying venous reflux.

Hi and Thank you for your question!
Consider a consultation with a vein specialist- board certified in venous and lymphatic medicine- to evaluate you. Ultrasound imaging of your lower extremities might be necessary to determine underlying vein process that might be causing the cosmetic sclerotherapy treatments you have had done to not give you an improved look. Based on clinical evaluation and imaging results, your physician is able to recommend best treatment plan for your specific case. It might be necessary to medically treat first the underlying venous reflux in order for the cosmetic treatment to improve appearance afterwards. Venous reflux can develop when the valves that keep venous blood flowing out of the legs and back to the heart no longer function, causing to pool in the legs and leading to signs and symptoms such as dilated veins that you can see closely to the skin, among others. Many factors contribute to this process. Vein specialist will discuss further with you about signs and symptoms, contributing factors, options to treatment, and preventive methods. 
All the best, 

I would highly recommend to see a vein specialist and get a complete ultrasound exam to determine large vein reflux. When done correctly, sclerotherapy should only improve your vein appearance. 

Hi Dear
I have to distinguish between residual spider veins and matting post procedure.
If any spider veins still visible after one procedure which is very common the best treatment is more sclerotherapy. Usually it takes 2-3 treatment to get rid of spider veins. But matting is increased small red vessels after sclerotherapy or EVLT which is called matting. you have to wait until susided before you do anything.
I think yours still spider veins that need more treatment.
Thank you
Ramtin Massoudi, MD