Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"
"doan thi van snippets" » "dan thi van snippets", "doanh tai van snippets", "hoang thi van snippets", "doan thi lan snippets", "doan thi hanh snippets", "doan thi nang 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: (((("doan thi van snippets") or ("python using java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("doan thi van snippets") OR ("python using java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( doan thi van snippets ) or ( python using java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doan thi van snippets") or ("python using java snippets"))) or ("locating bug core snippets"))*.