why are my find it difficult to secure a stable job.

hi guys,
I graduated since 2000,in a marketing major with upper credit from a reputable institution.also i have obtained addtional professional qualification like NIM,MNIMN,APCON while NIPR AND MBA are in view,but i still have not being able to secure a stable job.do you think there is some thing im not doing right.i have written series of job applications and also attended euoght job invitation interviews.

please,can u prefer a solution.

felix