Why does job discrimination persist despite the passage of the civil rights act 1964?

Jobs can "low key" discriminate against people under the pretense of something completely different. They have learned the loop holes through the hiring process. For example, if they feel the woman applicant has the talent and necessary skills to fulfill the job but the male applicant has the same skills and education; depending on the hiring individual they may be sexist against females. They can simply choose the male over the female and tell her that she wasn't qualified enough for the position.