There are several places you can go to search for part numbers. The most comprehensive available for free is Partminer: www.partminer.com. This is the old Cahners/IHS CAPSExpert database, with millions and millions of parts (and many versions of datasheets for many of them) dating back quite a while.
Searching by manufacturer's name is free; if you want to search by parametrics you have to pay.
You can also search on a variety of distributors' sites, including Avnet, Memec, Digikey, Mouser, etc.
Only after you've searched there should you ask in the forum for help finding a datasheet.