Perhaps you should try some spelling variations:
trang luan » tang luan, tranh luan, trang tuan
trinh luan » trinh luat, trinh quan, trinh han
duong tinh » duong minh, dong tinh, dung tinh
duong sinh » duong minh, duong manh, trong sinh
hien xanh » hien hanh, hien nhanh, chieu xanh
toan cau » 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: hoc hien xanh - hanh ((trang luan) or (trinh luan)) ung ((duong tinh) OR (duong sinh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh ((trang luan) OR (trinh luan)) ung ((duong tinh) OR (duong sinh)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - hanh ((trang luan) or (trinh luan)) ung ((duong tinh) OR (duong sinh)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh ((trang luan) or (trinh luan)) ung ((duong tinh) OR (duong sinh)) toan cau*.