Perhaps you should try some spelling variations:
"using java core snippets" » "using data core snippets"
"dong tham cau snippets" » "dong tam cau snippets", "hong tham cau snippets", "dong thap cau snippets", "dong tham canh snippets", "dong toan cau snippets", "dong cham cuu snippets"
"locating bug code 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 core snippets") or ("dong tham cau snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java core snippets") OR ("dong tham cau snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using java core snippets ) or ( dong tham cau snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java core snippets") or ("dong tham cau snippets"))) or ("locating bug code snippets"))*.