Animations gets separate

hi guys i am doing arrow shooting animation with fps hand but when i transfer it to unity the animations are separate like hand does his own move and arrow does his own i tried to make child of the hands but it didnt work

Welcome. Could you be more specific about how you went about setting up the animation?

im importing 2 different model they both have bones and im doing animation for both but when i expert to unity hand does doing animation without bow and bow do the same