Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban nuoc » ban duoc, ban nuoi, ban thuoc
dang thi » hoang thi, dang khoi
sach ky » sac ky, sach ty, sach kem
thi van » thi lan, thi hanh, thi nang
va dang » van dang, va nang, va lang
cua tre » cua te, cuu tre, dua tren
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: thuoc ((sach ky) or (sach y)) nang o hoi. thi van ban nuoc va dang thi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sach ky) OR (sach y)) nang o hoi. thi van ban nuoc va dang thi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sach ky) or (sach y)) nang o hoi. thi van ban nuoc va dang thi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sach ky) or (sach y)) nang o hoi. thi van ban nuoc va dang thi ((cua tre) OR (cua triet))*.