Perhaps you should try some spelling variations:
trinh hu » trinh chu, trinh tu, trinh he
tu sach » thu sach, su sach, te sach
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
va nam » van nam, ha nam
va nay » va ngay, va cay
tu lap » truc lap
hu cua » tu cua, vu 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 ((y nang) OR (ly nang)) xa hoi. hieu ((va nam) or (va nay)) tu lap trinh hu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (ly nang)) xa hoi. hieu ((va nam) OR (va nay)) tu lap trinh hu cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (ly nang)) xa hoi. hieu ((va nam) or (va nay)) tu lap trinh hu cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (ly nang)) xa hoi. hieu ((va nam) or (va nay)) tu lap trinh hu cua tre*.