Perhaps you should try some spelling variations:
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
vanh dai » vanh tai, lanh dao, van dao
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
van dai » van dao, van hai, can dai
cuu tre » cua tre, cau tren, cau treo
nang o » nang co, nang ho, nang ro
cac tu » cac thu, cach tu, cac du
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. lieu va ((cac nuoc) or (cac tu)) va ((vanh dai) OR (van dai)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang o hoi. lieu va ((cac nuoc) OR (cac tu)) va ((vanh dai) OR (van dai)) cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang o hoi. lieu va ((cac nuoc) or (cac tu)) va ((vanh dai) OR (van dai)) cuu tre*".