Is there a more effective way of thickening eye-brow?

I have thin eyebrows. Sometimes, I feel embarassed to ask my beautician to trim my eyebrow. There is practically nothing much to pluck, except for some hair growing on the upper lid that needs to be removed. With this kind of thinness, it takes some skill not to 'overtrim', alas not much hair will be left to be shaped.

I have to darken it a little to give it a sharper look with an eyebrow pencil. Otherwise, I will really look eyebrowless. So, this is a daily regime which I don't look forward to especially in days of blues. The stroke of the hand just doesn't seem right.

I was told that there is a type of liquid that can thicken eyebrow. This liquid is applied to the part where thickening is required, twice daily. My sister recommended it to me and she bought it from her beauty salon. She claimed that it worked on her eyebrow almost a few days after. I've tried for about more than a week but it doesn't seem to give any effect.