There's nothing to indicate that she can't, mk1, other than your own perspective;
Even within the human species, different people have differing muscle density and different upper capacity for how much stress they can consciously put their muscles under. Slender people can be functionally much stronger than people who look beefier, and it happens all the time.
For example... I'm 138cm tall, very petite... but I'm also fit and active, and stronger than I look; I can draw a 70cm draw-length long bow just fine, even with increased draw weight (albiet with a non-standard draw stance; the issue is the length of my arms, not the strength or ability to draw it), and I'm definitely slighter than that elf character.... who, is, by the way, an elf (or was identified as a wood elf in the original post); they are not humans and in their traditional lore are always stronger than their slender and lithe look suggests.
That said...
I'll be the first to wave a banner about places where their character models leave, shall we say, a
LOT to be desired...
Such as for Halflings
