Perhaps you should try some spelling variations:
thien van » thi van
thai cua » than cua, tai cuc, tri cua
ban thai » ban than, ban thi, ban tai
hieu van » hieu va, lieu va, hieu ve
tu sach » thu sach, su sach, te sach
xuc can » xuc ban, luc canh, luoc can
xuc cam » phuc cam
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
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 van) OR (thien van)) hau ((xuc can) or (xuc cam)) ban thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang o hoi. ((hieu van) OR (thien van)) hau ((xuc can) OR (xuc cam)) ban thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang o hoi. ((hieu van) OR (thien van)) hau ((xuc can) or (xuc cam)) ban thai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang o hoi. ((hieu van) OR (thien van)) hau ((xuc can) or (xuc cam)) ban thai cua tre*.