"boyish look" is correct and usable in written English.
You can use it as an adjective to describe someone's appearance. For example, "He had a carefree, boyish look on his face."
"Garçonne" read the headline on the program — meaning the boyish look tailor-made for women.
Palmer is an imposing, 6-foot-5, 235-pound athlete with a boyish look.
Springer is robust and serious, his dark brush-cut and large eyes giving him a boyish look.
The smaller proportions of the jackets lengthened the line and kept that boyish look he favors.
How did you come up with her almost boyish look? A. Do you know how that happened?
But as he has shed his boyish look, he has taken on a noticeable air of greater confidence.
At 54 he remains boyish looking.
BOYISH looks and wide eyes betray his lineage.
Dr. X, 30-something based on his boyish looks, was full of beans.
His boyish looks and low-key manner didn't immediately inspire confidence.
With his boyish looks, Mr. Weidmann sat and listened, sometimes staring into space.
