Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets", "python using java slippers"
"duc van sach snippets" » "duc ban sach snippets", "duc van hach snippets", "duc ngan sach snippets", "duc va sach snippets", "duc tan sach snippets", "duc manh sach snippets", "duc van sach slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (((("duc van sach snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duc van sach snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
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