Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
hieu hien » bieu hien, dieu hien, chieu chien
cau tren » cu tren, dau tren, ca tren
hien cac » thien cac, vien cac, hieu cac
kinh va » kinh van, sinh va, minh va
tinh va » tich va, trinh van, tinh gia
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
cac lao » ca lao, cac loai, cac giao
lang xa » lang ha, dang xay, lang van
ty lang » tay lang, ty xang, ty hang
lao va » tao va, cao va, bao va

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 ty lang xa hoi. hieu hien cac lao va ((kinh va) or (((tinh va) or (trinh vat)))) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty lang xa hoi. hieu hien cac lao va ((kinh va) OR (((tinh va) OR (trinh vat)))) cau tren.
• Adding a wildcard symbol may retrieve word variants: tu sach ty lang xa hoi. hieu hien cac lao va ((kinh va) or (((tinh va) or (trinh vat)))) cau tren*.