Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"duong hong son snippets" » "duong cong son snippets", "duong trong son snippets", "duong vuong son snippets", "duong hoang son snippets", "duong dong son snippets", "duong hang son snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code 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: (((("using java code snippets") or ("duong hong son snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("duong hong son snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( duong hong son snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("duong hong son snippets"))) or ("locating bug code snippets"))*.