Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"
"doi hoc sach snippets" » "doi hoc sinh snippets", "doi hoc cac snippets", "doi hoc anh snippets", "doi hoac sach snippets", "dai hoc sach snippets", "hoi hoc sach snippets"

Try widening your search to All Fields.

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