I’m lazy person.
Here are search engine providers for Firefox and MS IE web browsers.

I’ve added keywords for these search engines, like evt for Evita.lt, lmn for lemona.lt. Now, searching in particular site is as easy as Lotus 1-2-3: type in keyword and the term you need to search in the address bar. So, typing lmn ds180 will search for ds180 in Lemona.lt site.

Firefox Lemona.lt Evita.lt Datasheetcatalog.com
MS IE Lemona.lt Evita.lt Datasheetcatalog.com

Cheers.