one breed question

[LongHingKit]

I have four black&white tegu, three males, one female (male and female are born in 2009) since 2010, every year they will hibernate during winter. The three male tegus started to chase the female for mating since 2011, but it didn't last long. However, this year (2013) male tegus ' mating behavior is more and more intense, and the female tegu has not yet responded. This year I'm going to let them mating with each other. I put a male and the female tegu in the box (1900 cmx90cm), because I only have one female tegu, so I switch the male tegus every other week. unfortunately the male tegus were not so friendly, the female tegu was bitten pretty badly. Every time I see this I have to isolate them and put them back together again in a few days. The average temperatures here is 21 Celsius degree. In winter, temperatures is usually between 10 to 18 degrees, it will last about two months. My tegus start showing hibernation signs late October. They move slower and eat less. I wait until the end of the winter when the temperature is about 20 degrees I start to feed them. During hibernation I will use coconut soil and I will switch to sawdust after they become awake because sawdust is easier to clean up. Im using artificial light source, illumination time is 6 o 'clock a.m. to 6 o'clock p. m. Every day. i use common household light bulb, sometimes change to HAGEN UVB5.0 bulbs. I Don't know what the problem is. Is the hibernation or lighting made the female tegu has no sexual desire, or some other reasons? Please advise. I will be gratefully appreciated.