Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"tich toan cao snippets" » "tinh toan cao snippets", "tich than cao snippets", "trinh toan cao snippets", "tich toan ban snippets", "tich toan tap 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 ("tich toan cao snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("tich toan cao snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( tich toan cao snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("tich toan cao snippets"))) or ("locating bug code snippets"))*.