Searching imported mails finds results in mail titles only

Hello. After importing mails to Devonthink Pro 2.8.9 manually (new folder, drag mails from Apple Mail into that folder), search finds results only in mail titles (devonthink knows them as Name). Contents of those mails do not appear in search results. Why, and is there a way to fix this? Thanks.

Yes, but it will cost you to upgrade. Searching the content of emails is a DEVONthink Pro Office-only feature.

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