Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
cua nhung » va nhung
kinh cua » sinh cua, tinh cua, dinh cua
cong tam » cong tac, cong tan, cong nam
toan tap » toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo hieu lang - than kinh cua nhung ((cong tam) or (cong thanh)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - than kinh cua nhung ((cong tam) OR (cong thanh)) toan tap.
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - than kinh cua nhung ((cong tam) or (cong thanh)) toan tap*.