Good afternoon, how could I decrease the distance between the title and the search bar?
You can get some support from the item author:
You can utilize the plugins and custom CSS feature within WP itself to make modifications without the risk of creating any immediate challenges or problems when updating the theme.You can seek assistance from the author.
In theory, no. You may be adding more space. Easiest solution would contact the item author for the free support.
Also best not to go editing core files like style.css unless you know what you are doing.
If this is a WP theme then there are plugins and a custom CSS feature natively in WP where you can add changes without risking creating other immediate or when updating the theme challenges.
As @ki-themes said - if this is a new purchase then you have 6 months support so ask the author.