Perhaps you should try some spelling variations:
"arrest and assassination of ngo dinh dien" » "arrest and assassination of ngo tinh dien", "arrest and assassination of ngo kinh dien", "arrest and assassination of ngo dich dien", "arrest and assassination of nghi dinh dien", "arrest and assassination of ngoc minh dien", "arrest and assassination of nam dinh dien"
"arrest and assassinations of ngo dinh dien" » "arrest and assassinations of ngo tinh dien", "arrest and assassinations of ngo kinh dien", "arrest and assassinations of ngo dich dien", "arrest and assassinations of nghi dinh dien", "arrest and assassinations of ngoc minh dien", "arrest and assassinations of nam dinh dien"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("arrest and assassination of ngo dinh dien") OR ("arrest and assassinations of ngo dinh dien"))~.
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