Perhaps you should try some spelling variations:
vu sach » vu bach, su sach, vu khach
va hanh » van hanh, va thanh, va danh
cam luc » cam xuc, cau luc
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
so viet » hoc viet
ty tang » tay tang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, me hoi
luc va » duc va, tuc va, loc va
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ty tang ((ma hoi) or (ma hoa)). hieu ve cam luc va hanh vi ((su viet) or (so viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty tang ((ma hoi) OR (ma hoa)). hieu ve cam luc va hanh vi ((su viet) OR (so viet)).
• Adding a wildcard symbol may retrieve word variants: vu sach ty tang ((ma hoi) or (ma hoa)). hieu ve cam luc va hanh vi ((su viet) or (so viet))*.