Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dung lai » dung tai, dung lam, dung sai
thu xac » thau xay
cua tre » cua te, cuu tre, dua tren
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hieu he » hieu ve, hiem he, hieu le
cao hoc » co hoc, cho hoc, chat hoc
ty nang » ky nang, ty xang, ty hang
thu xa » thu ha, thu xe, thu ba
he nam » ha nam, nghe nam

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 nang cao hoc. hieu he nam ((thu xa) or (thu xac)) dung lai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang cao hoc. hieu he nam ((thu xa) OR (thu xac)) dung lai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang cao hoc. hieu he nam ((thu xa) or (thu xac)) dung lai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang cao hoc. hieu he nam ((thu xa) or (thu xac)) dung lai ((cua tre) OR (cua triet))*.