Perhaps you should try some spelling variations:
"doi cao cong snippets" » "doi cao code snippets", "doi cac cong snippets", "doi cao dang snippets", "doi cua cong snippets", "do cao cong snippets", "doi co cong snippets", "doc cao cong snippets"
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("python using java snippets") or ("doi cao cong snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("python using java snippets") OR ("doi cao cong snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( python using java snippets ) or ( doi cao cong snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python using java snippets") or ("doi cao cong snippets"))) or ("locating bug core snippets"))*.