Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh tai » thanh tai, hang tai, han tai
hieu va » lieu va, hieu qua
va chat » van chat, va phat, cao chat
sach ty » sach y, sach tu, sach thu
xuc van » luc van, xuc ban, thuc van
duc van » duc va, duc tan, duc manh
vuc van » luc van, thuc van, chuc van
ty nang » ky nang, ty xang, ty hang
tai cua » thai cua, tai cuc, tri cua
te sach » toc sach
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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 o hoi. hieu va chat ((((xuc van) OR (duc van))) or (vuc van)) hanh tai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang o hoi. hieu va chat ((((xuc van) OR (duc van))) OR (vuc van)) hanh tai cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang o hoi. hieu va chat ((((xuc van) OR (duc van))) or (vuc van)) hanh tai cua viet*".