Perhaps you should try some spelling variations:
cam truc » cau truc, nam truc, lam truoc
so sinh » so sanh, so tinh, cho sinh
ca viet » co viet, hoa viet, san viet
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
truc va » thuc va, thuc vat, trung va
hieu ve » hieu va, hieu van
va viet » hoa viet, san viet, mai viet
ly hang » ly quang
ma hoi » mai hoi, xa hoi, ma hoa
y nang » ky nang, ly nang, v nang
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: so sinh ((y nang) or (ly hang)) ma hoi. hieu ve cam truc va danh vi ((ca viet) OR (va viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sinh ((y nang) OR (ly hang)) ma hoi. hieu ve cam truc va danh vi ((ca viet) OR (va viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sinh ((y nang) or (ly hang)) ma hoi. hieu ve cam truc va danh vi ((ca viet) OR (va viet))".
• Adding a wildcard symbol may retrieve word variants: so sinh ((y nang) or (ly hang)) ma hoi. hieu ve cam truc va danh vi ((ca viet) OR (va viet))*.