Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet hach » thien hach, thuyet hach, thiet hai
tran thong » toan thong, tran phong, tran phuong
tran trong » gian trong, quan trong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tran hong » tran hoang, tranh hang
cong tac » cong ty
quan cau » quang cao, toan cau, quan ha

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet hach - thanh trung ((((tran thong) OR (tran hong))) or (tran trong)) cong tac quan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet hach - thanh trung ((((tran thong) OR (tran hong))) OR (tran trong)) cong tac quan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet hach - thanh trung ((((tran thong) OR (tran hong))) or (tran trong)) cong tac quan cau".
• Adding a wildcard symbol may retrieve word variants: hoc thiet hach - thanh trung ((((tran thong) OR (tran hong))) or (tran trong)) cong tac quan cau*.