Perhaps you should try some spelling variations:
trinh vi » trinh va, trinh ve, trinh viet
va trinh » van trinh, va tinh, lap trinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
sang ma » tang ma, nang ma, sang tao
ky sang » ky nang, ky dang, ky tang
ma hoi » mai hoi, xa hoi, ma hoa
cam ly » tam ly, cam ky, cam lo
vi cua » vai cua, di 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 sang ma hoi. ((hieu qua) or (lieu va)) ((cam lyc) or (cam ly)) va trinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang ma hoi. ((hieu qua) OR (lieu va)) ((cam lyc) OR (cam ly)) va trinh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang ma hoi. ((hieu qua) or (lieu va)) ((cam lyc) or (cam ly)) va trinh vi cua tre*.