Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets", "python using java slippers"
"len hoc sinh snippets" » "den hoc sinh snippets", "len hoa sinh snippets", "benh hoc sinh snippets", "len hoc dinh snippets", "len hoc minh snippets", "len hoc kinh snippets", "len hoc sinh 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: (((("len hoc sinh snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("len hoc sinh snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
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