I do see tiny white flies when I shake the plant. Also small white eggs on the bottom of some of the leaves.
Look under the leaves with a magnifying glass or jeweler's loop (about 30-60X magnification). You're looking for tiny little green larvae, or when adults the thrips have a flying stage. You may have both whiteflies and thrips.
Here's a pic of whitefly larvae/adult:
Whitefly damage, looks very similar to thrip damage.
And thrips:
Thrip damage:
Hope this helps, I couldn't find a good picture of whitefly damage.
