Troubleshooting search feature

I happened to be looking at a docx file in Devonthink when I searched a word from it and that file did not come up in the search results. With further trials, it doesn’t come up unless I search for the file title. This has me frightened that there are other files (particularly Word docs?) that aren’t coming up in searches. HOW DO I FIX THIS?!!!

What’s the search term? I successfully find .docx files here when searching content in DEVONthink Personal, Pro, and Pro Office.

PS: No need to shout. 8)