Perhaps you should try some spelling variations:
trinh do » trinh ky
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
nam tu » nam thuc
do cua » doi cua, co cua, de cua

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 ky) or (sac ky)) nang xa hoi. hieu va ((nam tu) OR (nam thu)) lap trinh do cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang xa hoi. hieu va ((nam tu) OR (nam thu)) lap trinh do cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang xa hoi. hieu va ((nam tu) OR (nam thu)) lap trinh do cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang xa hoi. hieu va ((nam tu) OR (nam thu)) lap trinh do cua tre*.