Perhaps you should try some spelling variations:
viet cua » viec cua, viet ca, biet cua
viet qua » vien quan, ket qua, viet ha
te sach » toc sach
ty nang » ty xang, ty hang, ly nang
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
va dinh » van dinh, va kinh, va tinh
ma hoi » mai hoi, xa hoi, ma hoa
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ty nang) or (ky nang)) ma hoi. hieu ve cac duc va dinh ((viet cua) OR (viet qua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ky nang)) ma hoi. hieu ve cac duc va dinh ((viet cua) OR (viet qua)) tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty nang) or (ky nang)) ma hoi. hieu ve cac duc va dinh ((viet cua) OR (viet qua)) tre*".