Companies are looking for two things, how qualified you are to solve the problem they have and how well you get along with people. Your resume should reflect both. Your language and demeanor should reflect both, and your enthusiasm about both will set you apart.
Develop an attitude of “realistic” optimism. No one, including recruiters, responds well to a sad or desperate candidate/applicant.
Research the company you are applying with to make sure you know what problem you can and will solve for them.