Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
trinh cua » tinh cua, trinh luat, trinh quan
cong vang » cong lang, cong quang, cong ngang
doc hieu » toc thieu, hoc thieu, hoc hien
dinh cua » dinh cuu, sinh cua, dinh cu
cong van » cong san, song van, cong tan
than tap » toan tap, han tap, phan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu xanh - hoang ((dinh cua) or (trinh cua)) nhung ((cong van) or (cong vang)) than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - hoang ((dinh cua) OR (trinh cua)) nhung ((cong van) OR (cong vang)) than tap.
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - hoang ((dinh cua) or (trinh cua)) nhung ((cong van) or (cong vang)) than tap*.