Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach thu » sach thue, sach thieu, sach tham
van hanh » van thanh, ban hanh, van anh
kham soc » cham soc, kham cuoc, ham so
cua tre » cua te, cuu tre, dua tren
soc van » hoc van, oc van, sac van
vu kham » vu khanh
so sach » so sanh, bo sach, co sach
lang ha » long ha
nang ma » tang ma, sang ma, nang cao
hieu vu » hieu va, hieu ve, hieu su

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thu ((nang ma) or (lang ha)) hoi. hieu vu kham soc van hanh vi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thu ((nang ma) OR (lang ha)) hoi. hieu vu kham soc van hanh vi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach thu ((nang ma) or (lang ha)) hoi. hieu vu kham soc van hanh vi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: so sach thu ((nang ma) or (lang ha)) hoi. hieu vu kham soc van hanh vi ((cua tre) OR (cua triet))*.