Perhaps you should try some spelling variations:
trong dang » truong dang, trong dan, trong dong
quang dung » quang trung, cuong dung
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
hoc hieu » hoc thieu, hoc hien, doc hieu
hieu cua » hieu qua, dieu cua, bieu cua
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: hoc hieu cua - hanh tinh ((quang dung) or (ung dung)) trong dang ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cua - hanh tinh ((quang dung) OR (ung dung)) trong dang ((toan cau) OR (toan ban)).
• Adding a wildcard symbol may retrieve word variants: hoc hieu cua - hanh tinh ((quang dung) or (ung dung)) trong dang ((toan cau) or (toan ban))*.