You are downloading the Searchum XAP file v220.127.116.11 for Windows Phone. Searchum is a free and useful Books & Reference app: A simple app for a fast search and research on the net. Its a live search app so needs a connection to the net all the time. A students friendly ... You can now download the offline XAP file to install & try it.
Download Locations for Searchum 18.104.22.168 XAP file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Searchum XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.