The pdf file is in (this assumes 64 bit), C: Program files, - Imsi Design - TCWP (or TCWD if deluxe) 2017 - Program64 - scroll down for tcw24.pdf.
You can copy and paste it somewhere, Or make a shortcut to is from the desktop, Or, in TC 2017, Options menu - (Program setup) General. Change the Help setting to use 'offline help', this last one will probably open the pdf in the normal acrobat reader.
For searching the online help, yeh, its not the best. To search just the 2017 docs, select search, and then advanced search (in the left hand pane), type in the search wanted, and under 'In Space' type 2017, then from the drop down that should appear select 2017 (English). bit of a pain really, so I usually just type in the normal search and scroll down the right hand pane until I find the correct version.