Perhaps you should try some spelling variations:
tang luan » dung luan
cac thoi » cac toi, cac hop, cac tro
tang dan » tang van, tung dan, tang quan
hoc khoi » hoc khoa, hoc hoa, hoc noi
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
vi cua » vai cua, di cua
xuc va » duc va, tuc va, luc va
va cam » va cham, va cac, va cao
cua su » qua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((hoc khoi) or (cac thoi)) ((tang dan) OR (tang luan)) hoi. hieu va cam xuc va hanh vi cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((hoc khoi) OR (cac thoi)) ((tang dan) OR (tang luan)) hoi. hieu va cam xuc va hanh vi cua su.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((hoc khoi) or (cac thoi)) ((tang dan) OR (tang luan)) hoi. hieu va cam xuc va hanh vi cua su".
• Adding a wildcard symbol may retrieve word variants: tu ((hoc khoi) or (cac thoi)) ((tang dan) OR (tang luan)) hoi. hieu va cam xuc va hanh vi cua su*.