Messages appearing in the quick search on iPhone cannot be deleted. We can only limit them by turning off the message search feature in the quick search (Spotlight) on the iPhone. To delete messages in the quick search on iPhone, follow these steps:
Step 1: On the Menu screen, go to Settings > General Settings
Step 2: Choose Search in Spotlight
Step 3: In the Spotlight Search Menu, you'll see a list of apps that Spotlight quick search will search. The Messages search item is at the bottom. Tap once to uncheck it.
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Here are tips on removing messages from the quick search on iPhone. From now on, you won't be startled by the appearance of secret messages. Although they are only displayed for a few first lines
