Perhaps you should try some spelling variations:
thanh lai » thanh hai, thanh lap, thanh loi
va thanh » gia thanh, ban thanh, va tinh
cham duc » pham duc, cham soc, pham duy
van cham » van chat, van tham, va cham
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
ca viet » va viet, co viet, hoa viet
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
lai ca » lai cua, lai cam, loai ca
x hoi » xa hoi, x ho
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: tu sach ty nang ((((x hoi) OR (5 hoi))) or (o hoi)). hieu van cham duc va thanh lai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((((x hoi) OR (5 hoi))) OR (o hoi)). hieu van cham duc va thanh lai ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((((x hoi) OR (5 hoi))) or (o hoi)). hieu van cham duc va thanh lai ca viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((((x hoi) OR (5 hoi))) or (o hoi)). hieu van cham duc va thanh lai ca viet*.