Perhaps you should try some spelling variations:
cong trong » cong thuong, duong trong, cong trinh
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
hanh hang » thanh hang, hang hang, hanh mang
trien van » thien van, trien san, trien nhan
hanh han » hanh nhan, hanh phan, hanh san
cau cong » cac cong, cuu cong, cao cong
trong ca » trong cac, trong nha
ca trien » va trien, ca tren, cua triet

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (hieu lang)) - ((hanh hang) OR (hanh han)) cau cong trong ca trien van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (hieu lang)) - ((hanh hang) OR (hanh han)) cau cong trong ca trien van~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (hieu lang)) - ((hanh hang) OR (hanh han)) cau cong trong ca trien van*.