Note: This answer is submitted as research and as partial answer for non number/currency type columns.
From my research til now it seems all columns except number and currency columns would be searchable. For number/currency columns we need to create managed property which is searchable to achieve same.
Unfortunately, at site collection we can only create managed properties of type text and yes/no type. When I mapped crawled properties - for currency columns - search didn't show anything after full crawl.
Next - Since mapping currency type crawled properties to text didn't show up anything after search, I'm looking for a method to enable this.
Pls. follow this great explanation by Mikael.