Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets", "python using java slippers"
"hen hoc sinh snippets" » "hen ho sinh snippets", "den hoc sinh snippets", "khien hoc sinh snippets", "hen hoc dinh snippets", "hen hoc minh snippets", "hen hoc kinh snippets", "hen 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: (((("hen 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: (((("hen hoc sinh snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
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