Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets"
"sach tao trinh snippets" » "sach tao tinh snippets", "sach tho trinh snippets", "sach giao trinh snippets", "sach dao trinh snippets", "sach bao trinh snippets", "sach tai trinh snippets"
"locating bug core snippets" » "locating bug 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 code snippets") or ("sach tao trinh snippets"))) or ("locating bug core snippets"))~.
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