Perhaps you should try some spelling variations:
doi chieu » doc hieu, ho chieu, mot chieu
tran tuan » tran xuan, tran quang, tran thanh
bang cong » dang cong, bang song, hang cong
tao trinh » tao tinh, tho trinh, giao trinh
trinh ban » trinh han, trinh san, trinh dan
hang cua » mang cua, hang ca, huong cua
cong tao » cong tac, cong tan, cong bao
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (doi chi)) xanh - hanh ((tran tuan) or (hang cua)) bang cong tao trinh ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doi chi)) xanh - hanh ((tran tuan) OR (hang cua)) bang cong tao trinh ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doi chi)) xanh - hanh ((tran tuan) or (hang cua)) bang cong tao trinh ban".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (doi chi)) xanh - hanh ((tran tuan) or (hang cua)) bang cong tao trinh ban*.