I added a column to my site collection then i made FULL CRAWL. now i am trying to go to see if i can have this column to filter with it in search web parts, i can't find it from the list of columns i can use. any help will be good. 

Hi,

If you have added a list column, then you need to create the managed property for that list column.  If it is site column then managed property will be automatically created for that site column.

In order to filter the columns within the search web parts, you need to managed property and in order to refine the data you managed property should be refinable option selected.

http://blogs.technet.com/b/tothesharepoint/archive/2013/03/06/from-site-column-to-managed-property-what-s-up-with-that.aspx

https://blogs.perficient.com/microsoft/2012/07/sp2013-search-quickie-createmap-a-new-managed-property-powershell/

Please don't forget to mark it as answered, if your problem resolved or helpful.

Hi tammy,

Make sure you have values for alteast one row for the column,Search creates a crawl property for that column during incremental crawl,after that u can map that crawl property with managed property and can use managed properties to filter .Crawled properties will be in format 'ows_column name'.https://samlman.wordpress.com/2015/03/02/creating-refinable-and-sortable-managed-properties-in-sites-and-site-collections-in-sharepoint-2013/