Perhaps you should try some spelling variations:
"trong duc toan snippets" » "trong duc code snippets", "trong duoc toan snippets", "trong dua toan snippets", "trong cuoc toan snippets", "trong duc tan snippets", "trong duc ton snippets", "trong duc hoan 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: (((("trong duc toan snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trong duc toan snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
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