What's Wrong with my Bearded Dragon?

We have two bearded dragons. Luna and Yoshi. Yoshi will only stay under the basking light. He refuses to stay under the UVB light. Even if we put him directly under it he will soon leave that spot and go back under the Basking Light unless we move him again. Luna is a different story. We will put her under the Basking Light to warm up (she's getting cold as of lately). She then leaves and goes to hide under a log (Uncovered, more of a climbing branch bought at PetCo) that's under the UVB. We are afraid she's not getting either now. All she wants to do is hide. We feed them Dubia Roaches and Juvenile Bearded Dragon Veggie Variety (freeze-dries vegetables and pellets). They really like both. We can't figure out what's wrong with our pair. They are both under a year old. Yoshi we got at PetCo. Luna we got from somebody on Craigslist who said they had gotten her from a breeder. We don't know what to do. Any suggestions?
We have resorted to putting the both in a smaller tank with nothing but a rock to bask on with both lights on top. So they have to get both.

They both have a 100W basking light and a 10.0 UVB T8 light.

Hi. If they are housed together they will both be happier in their own enclosure. Also the basking light and uvb need to be close to each other. So when they bask they receive heat and uvb. Also if your uvb is a coil/or compact. You need a better uvb. A reptisun 10.0 t5 long tube.