Perhaps you should try some spelling variations:
tdanh trung » thanh trung, thanh tung, dang trung
hieu quang » thieu quang, hieu quan, hieu qua
danh trung » dang trung, dinh trung, manh trung
nhung cong » dung cong, thong cong, hang cong
cua nhung » va nhung
hoc hieu » hoc thieu, hoc hien, doc hieu
cong tac » cong ty
tac vang » cac van, tac dung, tac dong
vang cau » hang cau, van cau, bang cau

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 quang - ((danh trung) or (tdanh trung)) cua nhung cong tac vang cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu quang - ((danh trung) OR (tdanh trung)) cua nhung cong tac vang cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu quang - ((danh trung) or (tdanh trung)) cua nhung cong tac vang cau*.