Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
van hanh » van thanh, ban hanh, van anh
vien cac » vien bach, vien dai, vien da
tu sach » thu sach, te sach, tu cach
xuc van » duc van, luc van, vuc van
cac xuc » cam xuc, cac nuoc, chat xuc
tu nano » truc nano
tu nang » tru nang, tu nong, tu lang
su sach » so sach, vu sach
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (su sach)) ((tu nang) OR (tu nano)) ma hoi. hieu vien cac xuc van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ((tu nang) OR (tu nano)) ma hoi. hieu vien cac xuc van hanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ((tu nang) OR (tu nano)) ma hoi. hieu vien cac xuc van hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ((tu nang) OR (tu nano)) ma hoi. hieu vien cac xuc van hanh vi cua vat*.