Perhaps you should try some spelling variations:
phuong thong » phuong trong, thong thong, phuong hoang
thong tran » thong than, thong tren, phuong tran
hieu lang » chieu sang, hieu quang, nhieu tang
trinh vat » trinh van, trinh luat, sinh vat
trinh va » trinh van, trinh ve, trinh vi
tran van » luan van
van chat » cao chat
ho hieu » ho chieu, hoi hieu, nho hieu

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh ((trinh va) OR (trinh vat)) phuong thong tran van chat~".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh ((trinh va) OR (trinh vat)) phuong thong tran van chat*.