If you are trying to type your colleague's name to share a video on Talent and the name is not coming up, it is usually due to one of two reasons:
1) Your colleague hasn't activated their Talent account yet. Your colleague needs to first activate their account using the link in the invitation email before you can share with them.
2) You are not in the same group as your colleague. Admins place Teachers and Coaches in groups based on their school, subject, grade level, or any other organizational category. In Talent, you can only share artifacts and give/elicit feedback from other users in your group(s). If you are not in the same group as someone you would like to share with, reach out to your System Admin to see if they can place you in the same group.