Perhaps you should try some spelling variations:
trung phan » trung thanh, dung phan, trung tuan
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
hoc hieu » hoc thieu, hoc hien, doc hieu
trung ha » trung hoc, trung tam, trung cap
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
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 hieu lang - hanh ((trung phan) or (trung ha)) nhung cong van toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - hanh ((trung phan) OR (trung ha)) nhung cong van toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - hanh ((trung phan) or (trung ha)) nhung cong van toan cau*.