Perhaps you should try some spelling variations:
cong vang » cong lang, cong quang, cong ngang
theo toc » ho toc, thac toc, theo bo
toc sach » hoc sach, doc sach, thuoc sach
thang va » hang va, trang va, thanh va
thong va » thong cua, truong va, thong qua
cong van » cong san, song van, cong tan
toan cao » toan ban, toan tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo toc sach - anh ((thang va) or (thong va)) nhung ((cong van) OR (cong vang)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo toc sach - anh ((thang va) OR (thong va)) nhung ((cong van) OR (cong vang)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo toc sach - anh ((thang va) or (thong va)) nhung ((cong van) OR (cong vang)) toan cao".
• Adding a wildcard symbol may retrieve word variants: theo toc sach - anh ((thang va) or (thong va)) nhung ((cong van) OR (cong vang)) toan cao*.