Perhaps you should try some spelling variations:
van hoach » van hach, van hoa, van hoc
ban thanh » ban hanh, ban hang
hoach dat » hoach xay, hoc dat, hoach va
thu sach » tu sach, thuat sach, thuoc sach
thanh vi » hanh vi, thanh va, thanh ve
hieu van » hieu va, thien van, lieu va
ty nang » ky nang, ty xang, ty hang
dat ban » bat ban, da ban, day ban
sach ty » sach y, sach tu, sach thu
vi cua » vai cua, di cua
me hoi » le hoi
ma hoi » mai hoi, ma hoa, va hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty nang ((((ma hoi) OR (me hoi))) or (xa hoi)). hieu van hoach dat ban thanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang ((((ma hoi) OR (me hoi))) OR (xa hoi)). hieu van hoach dat ban thanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang ((((ma hoi) OR (me hoi))) or (xa hoi)). hieu van hoach dat ban thanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang ((((ma hoi) OR (me hoi))) or (xa hoi)). hieu van hoach dat ban thanh vi cua vat*.