Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cua triet, dua tren
xuc van » duc van, luc van, xuc ban
cuu tre » cau tren, cau treo
ve cac » vien cac
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: tu sach ky nang o hoi. hieu ((ve cac) or (va cac)) xuc van hanh tai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang o hoi. hieu ((ve cac) OR (va cac)) xuc van hanh tai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang o hoi. hieu ((ve cac) or (va cac)) xuc van hanh tai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang o hoi. hieu ((ve cac) or (va cac)) xuc van hanh tai ((cua tre) OR (cuu tre))*.