You can initiate a standard search by pressing Ctrl-f, or
selecting the Edit > Search option from the menu. Advanced Search on the other hand is triggered with the shortcut Shift-Ctrl-f or via the Edit > Advanced Search menu.

Adobe Reader is not the only pdf reader that can find text in multiple pdf documents. Foxit Reader, a free pdf reading alternative, offers similar options. Foxit Reader users can use the shortcut Ctrl-Shift-f or select Tools > Search to open the search form of the program in a sidebar.

Adobe Reader opens the advanced search options in a new window. Here it is possible to switch from searching the current document to searching all pdfs in a folder on the hard drive. The folder is freely selectable, with My Documents being suggested by default.

A word or phrase needs to be entered into the search configuration form window. Expert users click on the Show More Options link at the bottom to display additional search filters and options.

Here it is then possible to include comments, attachments and bookmarks in the search, or search for whole words or case sensitive words only.

The more options page can be used to add additional search criteria, for instance to only search documents that have been created before or after a certain date, that have been written by a specific author or that contain object data or images.

It may take a while to scan the contents of all pdf documents that match the criteria. Adobe Reader displays the results in the same window. Results are sorted by document, and every instance of the word or phrase is shown on a separate line. A click on a line opens the containing page in the main Adobe Reader window.

Foxit Reader’s multi-pdf search options are limited in comparison. Here it is only possible to enter a search word or phrase, a directory that contains the pdf documents and a whole word and case sensitive filter.

Search results are displayed in a sidebar in the application window, a click puts the focus on the containing page. The search terms are highlighted by both applications on the pdf page.

Both programs are capable of finding text in multiple pdf documents. Users who need the additional filtering options find Adobe Reader’s pdf search more suitable as it offers more advanced options.

Are you using a different program or service to search for contents in multiple pdf documents? Let me know in the comments.

PDF Database is a web search engine for document formats. It concentrates on pdf and doc formats but you will find other formats in the database as well. The developers state that they have 7.5 million documents indexed at the moment. The main interface consists of a search form on top that can search for all document types or only for pdf or doc documents.

Below that is a search cloud that displays the last 200 searches that have been entered in the search form. The results page will display all documents that match the search. The format, name, size and url will be shown. Results can be sorted by size or name.

All tags that have been used to define the document are listed below and will load a new results page when clicked on. All documents found can be downloaded or viewed directly. The view option seems to only work if Adobe Reader and its web plugin have been installed.