Search will return results which contain any of the terms entered.
Example: 'speaking and listening' (without quotes) will find items which contain either 'speaking' or 'and' or 'listening'.
For an exact match, enclose in "".
Example: "speaking and listening" will find only pages which contain the phrase 'speaking and listening' (without quotes).
When searching a phrase (using quotes), results won't include instances where a word in that phrase is bold/italic/linked (because of the html tags).
Example: 'get updates by email or rss' can't be found (even though it's at the foot of every note).
There's no fix for this, and we'd rather you knew.
The workaround is to search for shorter phrases.