Perhaps you should try some spelling variations:
"using java core snippets" » "using data core snippets"
"dung mot thoi snippets" » "dung mo thoi snippets", "dung co thoi snippets", "dung dat thoi snippets", "dung moi thoi snippets", "dung mot khoi snippets", "dung mot tri snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (((("using java core snippets") or ("dung mot thoi snippets"))) or ("locating bug code snippets"))~.
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