The phrase "are too thin on" is correct and usable in written English.
It can be used to indicate that there is a lack of something, often referring to insufficient information or support.
Example: "The arguments presented in the report are too thin on evidence to be convincing."
Alternatives: "are lacking in" or "are insufficient in".
By the late summer of 2003, violence had risen considerably, and it became apparent that the British were too thin on the ground.
A pad that is too thin, on the other hand, may not provide enough cushioning and cause the carpet to wear prematurely.
Ingraham said that Palin is too thin on policy to be a credible presidential candidate.
If you'd like a top knot and your hair is too thin on its own to make a decent bun, you can use either a weft (extension) or a hair doughnut to help create the impression of more thickness.
Most of the cold environment strata, which formed on the outer shelf during oxygen-isotope stages 2 and 4, are too thin to be recognized on SIG 600J because of resolution, but corresponding erosion surfaces exist.
The numbers at the top of the game are too thin to expect an overnight renaissance on the back of a feelgood factor from his Wimbledon triumph, and all Murray can do is encourage the Lawn Tennis Association (LTA) to abandon their strategy of investing in players with little hope of making it and concentrating instead on spreading the game into parks and schools.
At some point during the interview the barman, who had known Polly most of her life, told her she was "too thin to go on tour".
And although parachutes are very effective in slowing down and stabilizing a Mars rover, the atmosphere is too thin to rely on them alone.
I was picked on for being too thin, for being feminine, for not liking football, for hanging round with girls, for having long hair.
But his resume is too thin for the nation to bet on his growing into the kind of leader he claims already to be.
