Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data snippets"
"hoc sach van snippets" » "hoc sinh van snippets", "hoc cac van snippets", "hoc anh van snippets", "hoc sach han snippets", "hoc sach va snippets", "hoc bach van 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: (((("hoc sach 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: (((("hoc sach van snippets") OR ("python using java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( hoc sach van snippets ) or ( python using java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hoc sach van snippets") or ("python using java snippets"))) or ("locating bug core snippets"))*.