Hi Sarit,
Welcome to this Microsoft Project newsgroup
I suspect you have resource levelled your project. Project puts in delays
to spread the work load and thus there are gaps in the flow of the critical
path. The only tasks showing critical are those directly attached to the
finish milestone.
FAQs, companion products and other useful Project information can be seen at
this web address:
http://project.mvps.org/faqs.htm
Hope this helps - please let us know how you get on
Mike Glen
MS Project MVP