Perhaps you should try some spelling variations:
hanh trinh » canh tranh
hien xanh » hien hanh, hien nhanh, chieu xanh
han huong » han thuong, han phuong, ban huong
anh tang » anh bang, anh dang, anh nang
luan han » luan hoan, luan phan, luan van
dan than » dan chan, ban than, van than
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: hoc hien xanh - ((anh tang) or (((hanh trinh) or (hanh chinh)))) luan han huong dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - ((anh tang) OR (((hanh trinh) OR (hanh chinh)))) luan han huong dan than tap.
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - ((anh tang) or (((hanh trinh) or (hanh chinh)))) luan han huong dan than tap*.