Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thuoc vat » thuc vat, thuoc va, thuoc bat
nam thuoc » nam thuc, nam thu, nha thuoc
dang xay » dang van, van xay
cua tre » cua te, cuu tre, dua tren
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
lang xa » lang ha, lang van
qua nam » quan nam, cua nam, quang nam
vat do » vat doi, vat co, vat da
do va » do van, so va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((lang xa) or (dang xay)) hoi. hieu qua nam thuoc vat do va ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((lang xa) OR (dang xay)) hoi. hieu qua nam thuoc vat do va ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: su sach ty ((lang xa) or (dang xay)) hoi. hieu qua nam thuoc vat do va ((cua tre) or (cua triet))*.