You will find the CHM version of the Harmony Help file (<harmony install path>/doc/help_harmony.chm) returns search results much faster than the PDF version.
The CHM help search provides some simple boolean search parameters (AND, OR, NOT, and NEAR). Here are some ways to leverage these boolean parameters in the MPLAB Harmony Help search:
If you are looking for information on the Watchdog Timer (WDT) Framework Libraries, enter "WDT NEAR "Framework" on the search line. It will return all WDT results in the Framework chapter and will filter out results in the other chapters.
If you want to search the help file for information regarding the example CAN applications (provided with the Harmony Framework), enter "CAN NEAR Applications Help" on the search line. This will return all results related to the CAN demos, and filters out the CAN Framework Library documentation.
The AND and OR booleans are not as useful for general searches because of the amount of information in the help. However, if you combine these with the Search Titles Only checkbox (bottom of search window), they can produce useful results too. The static and dynamic search takes you straight to the Static vs. Dynamic section when Search Titles Only is selected.
One of the most universal ways to leverage the search while coding is to search by layer and driver. For example, PLIB_ADC and DRV_USART. This is because a great starting point for each peripheral or driver is in the respective header file documentation that the help returns.
For more details on using the Harmony Help files, see the "Using the Help" section in the help file.