Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach tay » sach hay, sach nay, sach tai
xach tay » canh tay
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
dao hai » dao thai, dai hai, do hai
cua tre » cua te, cuu tre, dua tren
va hoc » van hoc
va dao » ca dao
nuoc » quoc, duoc, ngoc

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 tay) or (xach tay)) lang xa hoi. hieu va hoc nuoc va dao hai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tay) OR (xach tay)) lang xa hoi. hieu va hoc nuoc va dao hai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach tay) or (xach tay)) lang xa hoi. hieu va hoc nuoc va dao hai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach tay) or (xach tay)) lang xa hoi. hieu va hoc nuoc va dao hai ((cua tre) OR (cua triet))*.