Perhaps you should try some spelling variations:
"dung duc hoan snippets" » "dung duc code snippets", "duong duc hoan snippets", "dang duc hoan snippets", "dung du hoan snippets", "dung duc hoang snippets", "dung duc hoa snippets", "dung duc toan snippets"
"locating bug core snippets" » "locating bug code snippets"
"dung java java snippets" » "dung va java snippets"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (((("dung duc hoan snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
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