Perhaps you should try some spelling variations:
sach ty » sach y, sach tu, sach thu
vai cua » dai cua, hai cua, lai cua
duc ban » duc van, dua ban, duc man
vu sach » vu bach, su sach, vu khach
va cham » va chat, va tham
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, ma hoa
vi 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: vu sach ty nang ma hoi. hieu va cham ((duc ban) or (duc tan)) thanh ((vi cua) OR (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty nang ma hoi. hieu va cham ((duc ban) OR (duc tan)) thanh ((vi cua) OR (vai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ty nang ma hoi. hieu va cham ((duc ban) or (duc tan)) thanh ((vi cua) OR (vai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ty nang ma hoi. hieu va cham ((duc ban) or (duc tan)) thanh ((vi cua) OR (vai cua)) tre*.