Perhaps you should try some spelling variations:
"using hat cheo snippets" » "using hat code snippets", "using sat cheo snippets", "using data cheo snippets", "using half cheo snippets", "using thuat cheo snippets", "using nham cheo snippets", "using nhat nheo 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: (((("using hat cheo snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using hat cheo snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
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