Perhaps you should try some spelling variations:
phuong bang » phuong hoang, phuong giang, phuong quang
hieu quang » thieu quang, hieu quan, hieu qua
cuu phuong » cac phuong, thu phuong
hanh dung » thanh dung, anh dung, hanh dong
bang tinh » ban tinh, bang hinh, dang tinh
doc hieu » toc thieu, hoc thieu, hoc hien
dung cuu » dung cua, dung cu, dung cau
toan cau » toan cao, toan tap, toan tai
toan ban » van ban

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 quang - hanh dung cuu phuong bang tinh ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu quang - hanh dung cuu phuong bang tinh ((toan cau) OR (toan ban)).
• Adding a wildcard symbol may retrieve word variants: doc hieu quang - hanh dung cuu phuong bang tinh ((toan cau) or (toan ban))*.