Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
thien hieu » thien nhien, thien chien, thien hue
hieu lang » chieu sang, hieu quang, nhieu tang
doanh cua » doanh luan
manh cua » ban cua
cong san » cong tac
than tap » toan tap, phan tap, than cap
han tap » han tai, toan tap, nhan tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: thien hieu lang - lanh ((manh cua) or (doanh cua)) thong cong san ((than tap) OR (han tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien hieu lang - lanh ((manh cua) OR (doanh cua)) thong cong san ((than tap) OR (han tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thien hieu lang - lanh ((manh cua) or (doanh cua)) thong cong san ((than tap) OR (han tap))".
• Adding a wildcard symbol may retrieve word variants: thien hieu lang - lanh ((manh cua) or (doanh cua)) thong cong san ((than tap) OR (han tap))*.