Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"
"den hoc tran snippets" » "den hoc tan snippets", "den hoc tren snippets", "den boc tran snippets", "dien hoc tran snippets", "dan hoc tran snippets", "de hoc tran 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: (((("den hoc tran snippets") or ("python using java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("den hoc tran snippets") OR ("python using java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( den hoc tran snippets ) or ( python using java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("den hoc tran snippets") or ("python using java snippets"))) or ("locating bug core snippets"))*.