Answer: Your shrubs will fill out if you tip prune the branches (take a few inches off each). Wait until after flowering has finished to prune. I generally prune my camellias in March, just before new growth begins. You can use hedge trimmers if it's more convenient than pruning individual branches. As you cut the tips from each growing branch it will force new growth towards the center of the plant as well and additional branching at the tips of the stems. If you do this annually you'll eventually have a full, dense camellia shrub.
Best wishes with your landscape!
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