Perhaps you should try some spelling variations:
phuong tinh » phuong trinh, phuong binh, khuong tinh
dung phuong » dung thuong, bang phuong, dung chung
hieu lang » chieu sang, hieu quang, nhieu tang
doi hieu » doi chieu, doc hieu, doi hien
tang cua » mang cua, hang cua, tang luan
toan cau » toan cao, toan ban, toan tap
ban cua » ban quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi hieu lang - hanh ((tang cua) or (ban cua)) dung phuong tinh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - hanh ((tang cua) OR (ban cua)) dung phuong tinh toan cau.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - hanh ((tang cua) or (ban cua)) dung phuong tinh toan cau*.