Users believe they are doing a full text search when they are actually doing a titles search by hitting enter or clicking on the titles button.
Observation
This has happened twice. When the user asked how to find a specific page, I pointed out the search box. In one case, the user typed in text that obviously wasn't intended to be a title search (afterwards the user also confirmed that wasn't their intent) and hit enter. In the other, the user actually clicked on the "titles" button (apparently not reading or not understanding it) and expected a keyword search. (He was surprised that a particular page didn't appear in the results since he had seen that word in the text.)
Task
Search the wiki site.
Users
The users have technical backgrounds (engineering and science), but are not programmers. They use email and frequent web sites, but are new to wikis and online forums in general.
Context
Observations were made over-the-shoulder in their offices.
MoinMoin 1.3.4. Sinorca4Moin theme.
One observation was with Safari on a Mac. Another was Internet Explorer on Windows XP.
Discussion
I believe that the users have been conditioned to expect a keyword search and they expect the default search to be keyword. These users also expect hitting enter or the left button to do what they expect. Neither the word "titles" or "text" meant anything to them and they expected hitting the left button would do what they expect from a search. This reference might be applicable. Despite, the expectation of a full text search, the expense on MoinMoin still might be high enough to consider whether or not that should be the default. Twiki seems to use a full text search, with a "jump" search box appearing on the search page after the full-text search has been conducted. Wikipedia uses "Go" as the left button (and default) and the more familiar "Search" as the right button.
Its a known problem, see UnifySearch