When I select a tag link, result shows the title and content. How can I change the list of related article appears only with title and not include any content please?
There are a few ways to achieve that.
First and the easiest way is to go to the display settings of the content type and hide all fields in teaser view mode.
Second way is to use Views module, which ships with a taxonomy term view. You need to go to the views administration,
structure/views, and enable this view. Or better, clone this view and enable the cloned one. This way you have more options then only to show the titles. However, it can be an overkill if you only need to show titles.
tvi module should meet your needs.
The TVI (Taxonomy Views Integrator) module allows selective overriding of taxonomy terms and/or vocabulary with the view of your choice. Using TVI you can easily create custom views to output all terms in X vocabulary.
The module's documentation (setup, configuration etc) is so well written, extensive and detailed that I found no reason to repeat it here.