Perhaps you should try some spelling variations:
"hoc cao cong snippets" » "hoc cao code snippets", "hoc cac cong snippets", "hoc cao dang snippets", "hoc cua cong snippets"
"locating bug core snippets" » "locating bug code snippets"
"python using data snippets" » "python using java snippets", "python using sat snippets", "python missing data snippets"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (((("hoc cao cong snippets") or ("python using data snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hoc cao cong snippets") OR ("python using data snippets"))) OR ("locating bug core snippets")).
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