Perhaps you should try some spelling variations:
"using java core snippets" » "using data core snippets"
"hoc can tra snippets" » "hoc dan tra snippets", "hoc cao tra snippets", "hoc cac tra snippets", "hoc ca tra snippets", "hoc cau tra snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets"

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

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